Updated on 2025/05/22

写真a

 
FUJITA MEGUMI
 
Affiliation
Faculty of Medicine, Center for Medical Education, Assistant Professor
Title
Assistant Professor
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Papers

  • The Role of CNS in the Effects of Salt on Blood Pressure. International journal

    Megumi Fujita, Toshiro Fujita

    Current hypertension reports   18 ( 2 )   10 - 10   2016.2

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    Sympathetic nerve activity is involved in the pathogenesis of salt-sensitive hypertension. The central nervous system, which regulates sympathetic nerve activity and blood pressure, plays a pivotal role. Central sympathoexcitation is deeply involved in the pathogenesis of salt-sensitive hypertension, although the precise mechanisms have not been fully elucidated because of their complexity. The role of brain oxidative stress in sympathoexcitation has been suggested in some types of hypertensive animal models. We have shown that increased brain oxidative stress may elevate arterial pressure through central sympathoexcitation in salt-sensitive hypertension. Several other factors such as mineralocorticoid receptors, aldosterone, corticosterone, epithelial sodium channels, and angiotensin II also play important roles in central sympathetic activation, some of which can be associated with brain oxidative stress. Furthermore, brain paraventricular nucleus Gαi2-protein-mediated transduction has been recently reported as a candidate for the molecular mechanism countering the development of salt-sensitive hypertension.

    DOI: 10.1007/s11906-015-0620-7

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  • The role of CNS in salt-sensitive hypertension. International journal

    Megumi Fujita, Toshiro Fujita

    Current hypertension reports   15 ( 4 )   390 - 4   2013.8

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    The role of sympathetic nerve activity in hypertension is currently receiving increased attention, because catheter-based renal denervation was recently shown to reduce blood pressure safely in patients with treatment-resistant hypertension. The central nervous system, which regulates sympathetic nerve activity and blood pressure, is pivotal. Central sympathoexcitation has been shown to be deeply involved in the pathogenesis of salt-sensitive hypertension, although its precise mechanisms have not yet been fully elucidated due to their complexity. Recently, a role for brain oxidative stress in sympathoexcitation has been suggested in some hypertensive animal models. We have demonstrated that increased brain oxidative stress may elevate arterial pressure through central sympathoexcitation in salt-sensitive hypertension. Several factors other than oxidative stress have also been shown to play important roles in central sympathetic activation. In the future, strategies may be developed to elicit a sympathetic inhibition by modulating these factors to prevent and manage salt-sensitive hypertension.

    DOI: 10.1007/s11906-013-0358-z

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  • Sympathoexcitation by brain oxidative stress mediates arterial pressure elevation in salt-induced chronic kidney disease. International journal

    Megumi Fujita, Katsuyuki Ando, Hiroo Kawarazaki, Chiaki Kawarasaki, Kazuhiko Muraoka, Hiroshi Ohtsu, Hideki Shimizu, Toshiro Fujita

    Hypertension (Dallas, Tex. : 1979)   59 ( 1 )   105 - 12   2012.1

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    Hypertension is very prevalent in chronic kidney disease and critical for its prognosis. Sympathoexcitation and oxidative stress have been demonstrated to be involved in chronic kidney disease. We have shown previously that sympathoexcitation by brain oxidative stress mediates arterial pressure elevation in the salt-sensitive hypertension model, Dahl salt-sensitive rats. Thus, we investigated whether sympathoexcitation by excessive brain oxidative stress could contribute to arterial pressure elevation in salt-induced chronic kidney disease model rats. Young (3-week-old) male Sprague-Dawley rats were randomly assigned to a uninephrectomy or sham operation and then subjected to either a normal salt (0.5%) or high-salt (8.0%) diet for 4 weeks. The young salt-loaded uninephrectomized rats exhibited sympathoexcitation, hypertension, and renal injury, proteinuria and global glomerulosclerosis together with tubulointerstitial damage. Under urethane anesthesia and artificial ventilation, renal sympathetic nerve activity, arterial pressure, and heart rate decreased to a greater degree in the salt-loaded uninephrectomized rats than in the nonsalt-loaded uninephrectomized rats and the salt-loaded or nonsalt-loaded sham-operated rats, when Tempol, a membrane-permeable superoxide dismutase mimetic, was infused acutely into the lateral cerebral ventricle. Oxidative stress in the hypothalamus, measured by lucigenin chemiluminescence, was also significantly greater. Furthermore, in the salt-loaded uninephrectomized rats, antioxidant treatment with chronic intracerebroventricular Tempol decreased sympathetic nerve activity and arterial pressure, which, in turn, led to a decrease in renal damage. Similar effects were elicited by treatment with oral moxonidine, the central sympatholytic agent. In conclusion, sympathoexcitation by brain oxidative stress may mediate arterial pressure elevation in salt-induced chronic kidney disease.

    DOI: 10.1161/HYPERTENSIONAHA.111.182923

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  • Reactive oxygen species and the central nervous system in salt-sensitive hypertension: possible relationship with obesity-induced hypertension. International journal

    Katsuyuki Ando, Megumi Fujita

    Clinical and experimental pharmacology & physiology   39 ( 1 )   111 - 6   2012.1

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    1. There are multiple and complex mechanisms of salt-induced hypertension; however, central sympathoexcitation plays an important role. In addition, the production of reactive oxygen species (ROS) is increased in salt-sensitive hypertensive humans and animals. Thus, we hypothesized that brain ROS overproduction may increase blood pressure (BP) by central sympathostimulation. 2. Recently, we demonstrated that ROS levels were elevated in the hypothalamus of salt-sensitive hypertensive animals. Moreover, intracerebroventricular anti-oxidants suppressed BP and renal sympathetic nerve activity more in salt-sensitive than non-salt-sensitive hypertensive rats. Thus, brain ROS overproduction increased BP through central sympathoexcitation in salt-sensitive hypertension. 3. Salt sensitivity of BP is enhanced in obesity and metabolic syndrome. Interestingly, it is also suggested that, in obesity-induced hypertension models, increases in BP are caused by brain ROS-induced central sympathoexcitation. 4. Recent studies suggest that increased ROS production in the brain and central sympathoexcitation may share a common pathway that increases BP in both salt- and obesity-induced hypertension.

    DOI: 10.1111/j.1440-1681.2011.05510.x

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  • Sympathoexcitation by oxidative stress in the brain mediates arterial pressure elevation in obesity-induced hypertension. International journal

    Ai Nagae, Megumi Fujita, Hiroo Kawarazaki, Hiromitsu Matsui, Katsuyuki Ando, Toshiro Fujita

    Circulation   119 ( 7 )   978 - 86   2009.2

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    BACKGROUND: Obesity is one of the major risk factors for cardiovascular disease and is often associated with increased oxidative stress and sympathoexcitation. We have already suggested that increased oxidative stress in the brain modulates the sympathetic regulation of arterial pressure in salt-sensitive hypertension, which is often associated with obesity. The present study was performed to determine whether oxidative stress could mediate central sympathoexcitation in the initial stage of obesity-induced hypertension. METHODS AND RESULTS: Four-week-old male Sprague-Dawley rats were fed a high-fat (45% kcal as fat) or low-fat (10% kcal as fat) diet for 6 weeks. Fat loading elicited hypertension and sympathoexcitation, along with visceral obesity. In urethane-anesthetized and artificially ventilated rats, arterial pressure and renal sympathetic nerve activity decreased in a dose-dependent fashion when 53 or 105 mumol/kg tempol, a membrane-permeable superoxide dismutase mimetic, was infused into the lateral cerebral ventricle. Central tempol reduced arterial pressure and renal sympathetic nerve activity to a significantly greater extent in high-fat diet-fed hypertensive rats than in low-fat diet-fed normotensive rats. Intracerebroventricular apocynin or diphenyleneiodonium, a reduced NADPH oxidase inhibitor, also elicited markedly greater reductions in arterial pressure and renal sympathetic nerve activity in the high-fat diet-fed rats. In addition, fat loading increased NADPH oxidase activity and NADPH oxidase subunit p22(phox), p47(phox), and gp91(phox) mRNA expression in the hypothalamus. CONCLUSIONS: In obesity-induced hypertension, increased oxidative stress in the brain, possibly via activation of NADPH oxidase, may contribute to the progression of hypertension through central sympathoexcitation.

    DOI: 10.1161/CIRCULATIONAHA.108.824730

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  • Sympathoexcitation by oxidative stress in the brain mediates arterial pressure elevation in salt-sensitive hypertension. International journal

    Megumi Fujita, Katsuyuki Ando, Ai Nagae, Toshiro Fujita

    Hypertension (Dallas, Tex. : 1979)   50 ( 2 )   360 - 7   2007.8

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    Central sympathoexcitation is involved in the pathogenesis of salt-sensitive hypertension. We have suggested that oxidative stress in the brain modulates the sympathetic regulation of arterial pressure. Thus, we investigated whether oxidative stress could mediate central sympathoexcitation in salt-sensitive hypertension. Five- to 6-week-old male Dahl salt-sensitive rats and salt-resistant rats were fed with a normal (0.3%) or high- (8%) salt diet for 4 weeks. In urethane-anesthetized and artificially ventilated rats, arterial pressure, renal sympathetic nerve activity, and heart rate decreased in a dose-dependent fashion, when 20 or 40 micromol of tempol, a membrane-permeable superoxide dismutase mimetic, was infused into the lateral cerebral ventricle. The same degree of reduction was noted in salt-sensitive and salt-resistant rats without salt loading. Salt loading significantly increased central tempol-induced reductions in arterial pressure (-29.1+/-4.8% versus -10.6+/-3.3% at 40 micromol; P<0.01), sympathetic nerve activity (-18.7+/-2.0% versus -7.1+/-1.8%; P<0.01), and heart rate (-10.7+/-2.8% versus -2.0+/-0.7%; P<0.05) in salt-sensitive rats but not in salt-resistant rats. Intracerebroventricular diphenyleneiodonium, a reduced nicotinamide-adenine dinucleotide phosphate oxidase inhibitor, also elicited significantly greater reduction in each parameter in salt-loaded salt-sensitive rats. Moreover, salt loading increased reduced nicotinamide-adenine dinucleotide phosphate-dependent superoxide production in the hypothalamus in salt-sensitive rats but not in salt-resistant rats. In addition, reduced nicotinamide-adenine dinucleotide phosphate oxidase subunits p22(phox), p47(phox), and gp91(phox) mRNA expression significantly increased in the hypothalamus of salt-loaded salt-sensitive rats. In conclusion, in salt-sensitive hypertension, increased oxidative stress in the brain, possibly via activation of reduced nicotinamide-adenine dinucleotide phosphate oxidase, may elevate arterial pressure through central sympathoexcitation.

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  • [Adrenal medullary hyperplasia].

    Megumi Fujita, Katsuyuki Ando, Toshiro Fujita

    Nihon rinsho. Japanese journal of clinical medicine   Suppl 1   744 - 6   2006.5

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  • Sympatho-inhibitory action of endogenous adrenomedullin through inhibition of oxidative stress in the brain. International journal

    Megumi Fujita, Tomoyuki Kuwaki, Katsuyuki Ando, Toshiro Fujita

    Hypertension (Dallas, Tex. : 1979)   45 ( 6 )   1165 - 72   2005.6

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    Central sympathetic activation is one of the possible mechanisms underlying hypertension, in which reactive oxygen species may play a role. Thus, we examined whether adrenomedullin, an antioxidant peptide, is involved in the central regulation of arterial pressure through sympatho-modulatory action. Adrenomedullin knockout mice were fed with high-salt diet for 4 weeks to stimulate adrenomedullin production. In the wild-type littermates, brain adrenomedullin content was significantly increased with salt loading, but not in the knockout mice. Intracerebroventricular hyperosmotic saline increased arterial pressure and sympathetic nerve activity in a dose-dependent fashion. With the normal salt diet, the hyperosmotic saline-induced response did not significantly differ between the knockout and wild-type mice; with the high-salt diet, however, the response was significantly greater in the knockout mice than in wild-type littermates (arterial pressure: 35.3+/-5.7% versus 20.1+/-2.1%, P<0.05; sympathetic nerve activity: 30.3+/-4.8% versus 15.9+/-1.5%, P<0.05; respectively). Moreover, pretreatment with 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl (tempol), a membrane-permeable superoxide dismutase mimetic, inhibited the augmented response to central hyperosmotic saline in salt-loaded knockout mice. Consistently, the hyperosmotic saline-induced production of reactive oxygen species, measured by the lucigenin chemiluminescence method, was significantly greater in the isolated hypothalamus of salt-loaded knockout mice than in that of salt-loaded wild-type ones. In conclusion, endogenous adrenomedullin in the brain may inhibit sympathetic activation through its antioxidant action.

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  • Recurrent bilateral adrenal infarction with myelodysplastic/myeloproliferative neoplasm-unclassifiable (MDS/MPN-U): a case report. International journal

    Yoshitomo Hoshino, Katsunori Manaka, Junichiro Sato, Yui Asatsuma, Hirofumi Horikoshi, Maki Takeuchi, Nobuaki Ito, Megumi Fujita, Megumi Yasunaga, Kensuke Matsuda, Akira Honda, Hiroaki Maki, Yosuke Masamoto, Mineo Kurokawa, Masaomi Nangaku, Noriko Makita

    BMC endocrine disorders   23 ( 1 )   128 - 128   2023.6

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    BACKGROUND: Bilateral adrenal infarction is rare and only a small number of cases have been reported so far. Adrenal infarction is usually caused by thrombophilia or a hypercoagulable state, such as antiphospholipid antibody syndrome, pregnancy, and coronavirus disease 2019. However, adrenal infarction with myelodysplastic/myeloproliferative neoplasm (MDS/MPN) has not been reported. CASE PRESENTATION: An 81-year-old man with a sudden severe bilateral backache presented to our hospital. Contrast-enhanced computed tomography (CT) led to the diagnosis of bilateral adrenal infarction. Previously reported causes of adrenal infarction were all excluded and a diagnosis of MDS/MPN-unclassifiable (MDS/MPN-U) was reached, which was considered to be attributed to adrenal infarction. He developed a relapse of bilateral adrenal infarction, and aspirin administration was initiated. Partial primary adrenal insufficiency was suspected as the serum adrenocorticotropic hormone level was persistently high after the second bilateral adrenal infarction. CONCLUSION: This is the first case of bilateral adrenal infarction with MDS/MPN-U encountered. MDS/MPN has the clinical characteristics of MPN. It is reasonable to assume that MDS/MPN-U may have influenced bilateral adrenal infarction development, considering the absence of thrombosis history and a current comorbid hypercoagulable disease. This is also the first case of recurrent bilateral adrenal infarction. It is important to carefully investigate the underlying cause of adrenal infarction once adrenal infarction is diagnosed, as well as to assess adrenocortical function.

    DOI: 10.1186/s12902-023-01384-5

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  • A hyperaldosteronism subtypes predictive model using ensemble learning. International journal

    Shigehiro Karashima, Masaki Kawakami, Hidetaka Nambo, Mitsuhiro Kometani, Isao Kurihara, Takamasa Ichijo, Takuyuki Katabami, Mika Tsuiki, Norio Wada, Kenji Oki, Yoshihiro Ogawa, Ryuji Okamoto, Kouichi Tamura, Nobuya Inagaki, Takanobu Yoshimoto, Hiroki Kobayashi, Miki Kakutani, Megumi Fujita, Shoichiro Izawa, Tetsuya Suwa, Kohei Kamemura, Masanobu Yamada, Akiyo Tanabe, Mitsuhide Naruse, Takashi Yoneda

    Scientific reports   13 ( 1 )   3043 - 3043   2023.2

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    This study aimed to develop a machine-learning algorithm to diagnose aldosterone-producing adenoma (APA) for predicting APA probabilities. A retrospective cross-sectional analysis of the Japan Rare/Intractable Adrenal Diseases Study dataset was performed using the nationwide PA registry in Japan comprised of 41 centers. Patients treated between January 2006 and December 2019 were included. Forty-six features at screening and 13 features at confirmatory test were used for model development to calculate APA probability. Seven machine-learning programs were combined to develop the ensemble-learning model (ELM), which was externally validated. The strongest predictive factors for APA were serum potassium (s-K) at first visit, s-K after medication, plasma aldosterone concentration, aldosterone-to-renin ratio, and potassium supplementation dose. The average performance of the screening model had an AUC of 0.899; the confirmatory test model had an AUC of 0.913. In the external validation, the AUC was 0.964 in the screening model using an APA probability of 0.17. The clinical findings at screening predicted the diagnosis of APA with high accuracy. This novel algorithm can support the PA practice in primary care settings and prevent potentially curable APA patients from falling outside the PA diagnostic flowchart.

    DOI: 10.1038/s41598-023-29653-2

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  • Effect of Intraprocedural Cortisol Measurement on ACTH-stimulated Adrenal Vein Sampling in Primary Aldosteronism. International journal

    Mitsuhiro Kometani, Takashi Yoneda, Shigehiro Karashima, Yoshiyu Takeda, Mika Tsuiki, Akihiro Yasoda, Isao Kurihara, Norio Wada, Takuyuki Katabami, Masakatsu Sone, Takamasa Ichijo, Kouichi Tamura, Yoshihiro Ogawa, Hiroki Kobayashi, Shintaro Okamura, Nobuya Inagaki, Junji Kawashima, Megumi Fujita, Kenji Oki, Yuichi Matsuda, Akiyo Tanabe, Mitsuhide Naruse

    Journal of the Endocrine Society   6 ( 9 )   bvac104   2022.9

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    CONTEXT: Adrenocorticotropin (ACTH) loading is used to increase the success rate of adrenal vein sampling (AVS). OBJECTIVE: We aimed to determine the effect of intraprocedural cortisol measurement (ICM) on ACTH-stimulated AVS (AS-AVS) owing to a lack of reliable data on this topic. METHODS: This multicenter, retrospective, observational study took place in 28 tertiary centers in Japan. Among 4057 patients enrolled, 2396 received both basal AVS (B-AVS) and AS-AVS and were divided into 2 groups according to whether ICM was used. The effect of ICM on AS-AVS was measured. RESULTS: In patients who underwent both AVS procedures, the ICM group had significantly higher success rates for both B-AVS and AS-AVS than the non-ICM group did. However, the probability of failure of AS-AVS after a successful B-AVS and the probability of success of AS-AVS after a failed B-AVS were not significantly different in the 2 groups. For subtype diagnosis, propensity-score matching revealed no significant difference between the 2 groups, and the discrepancy rate between B-AVS and AS-AVS for subtype diagnosis was also not significantly different. CONCLUSION: ICM significantly increased the success rate of B-AVS and AS-AVS in protocols in which both AVS procedures were performed and had no effect on subtype diagnosis. However, in protocols in which both AVS procedures were performed, the results suggest ICM may not be necessary when performing AS-AVS if ICM is used only when B-AVS is performed. Our study suggests that ICM during AVS plays an important role and should be recommended.

    DOI: 10.1210/jendso/bvac104

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  • Age-stratified comparison of clinical outcomes between medical and surgical treatments in patients with unilateral primary aldosteronism. International journal

    Ryo Nakamaru, Koichi Yamamoto, Hiroshi Akasaka, Hiromi Rakugi, Isao Kurihara, Takashi Yoneda, Takamasa Ichijo, Takuyuki Katabami, Mika Tsuiki, Norio Wada, Tetsuya Yamada, Hiroki Kobayashi, Kouichi Tamura, Yoshihiro Ogawa, Junji Kawashima, Nobuya Inagaki, Megumi Fujita, Minemori Watanabe, Kohei Kamemura, Shintaro Okamura, Akiyo Tanabe, Mitsuhide Naruse

    Scientific reports   11 ( 1 )   6925 - 6925   2021.3

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    Although adrenalectomy (ADX) is an established treatment for unilateral primary aldosteronism (uPA), the influence of age on the surgical outcomes is poorly understood. Therefore, we aimed to elucidate how age affects the clinical outcomes after treatments. We analyzed 153 older (≥ 65 years) and 702 younger patients (< 65 years) with uPA, treated either with ADX or mineralocorticoid receptor antagonist (MRA) in the Japan PA Study, and compared the estimated glomerular filtration rate (eGFR) or blood pressure over a 36-month period after treatments. ADX-treated patients showed severer biochemical indicators than MRA-treated patients. During 6 and 36 months, the eGFR decreased more prominently in older but not in younger patients with ADX than in those with MRA, which remained significant after adjustment with the inverse probability of treatment weighting (IPTW). There was a significant interaction between the age-groups and the treatment choices in the change of the eGFR with IPTW-adjusted analysis. The post-treatment dose of antihypertensive medication was lower in younger and higher in older patients with ADX than those with MRA. The clinical benefit of ADX differed between younger and older patients with uPA. These findings indicate the need for further validation on whether ADX can benefit older patients with uPA.

    DOI: 10.1038/s41598-021-86290-3

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  • Sex Differences in Renal Outcomes After Medical Treatment for Bilateral Primary Aldosteronism. International journal

    Ryo Nakamaru, Koichi Yamamoto, Hiroshi Akasaka, Hiromi Rakugi, Isao Kurihara, Takashi Yoneda, Takamasa Ichijo, Takuyuki Katabami, Mika Tsuiki, Norio Wada, Tetsuya Yamada, Hiroki Kobayashi, Kouichi Tamura, Yoshihiro Ogawa, Junji Kawashima, Nobuya Inagaki, Megumi Fujita, Kenji Oki, Kohei Kamemura, Akiyo Tanabe, Mitsuhide Naruse

    Hypertension (Dallas, Tex. : 1979)   77 ( 2 )   537 - 545   2021.2

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    A higher incidence of bilateral primary aldosteronism in women is reported. Treatment of bilateral primary aldosteronism usually involves mineralocorticoid receptor antagonists. However, the impact of sex on renal outcomes is unknown. We compared renal outcomes between the sexes after mineralocorticoid receptor antagonist initiation by analyzing data obtained from 415 female and 313 male patients with bilateral primary aldosteronism who were treated with spironolactone or eplerenone in the JPAS (Japan Primary Aldosteronism Study). Over the course of 5 years, the temporal reduction in the estimated glomerular filtration rate was greater in women than in men (P<0.001). Systolic blood pressure levels were equal between the sexes, despite higher doses of antihypertensive drugs in men. The mean of the annual decline in estimated glomerular filtration rate during what we termed the late phase, or 6 to 60 months after mineralocorticoid receptor antagonist initiation, was larger in women than in men after adjusting for patient characteristics (-1.33 mL/min per 1.73 m2 per year versus -1.04 mL/min per 1.73 m2 per year, P<0.01). Female sex was a significant predictor of greater annual decline during the late phase in patients taking spironolactone but not in those taking eplerenone. Spironolactone use and diabetes were independent predictors of a greater annual decline in estimated glomerular filtration rate during the late phase in women. These findings suggest that female sex is associated with poorer renal outcomes in patients receiving mineralocorticoid receptor antagonist for bilateral primary aldosteronism.

    DOI: 10.1161/HYPERTENSIONAHA.120.16449

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  • Obesity predicts persistence of resistant hypertension after surgery in patients with primary aldosteronism. International journal

    Ryo Nakamaru, Koichi Yamamoto, Hiromi Rakugi, Hiroshi Akasaka, Isao Kurihara, Takamasa Ichijo, Yoshiyu Takeda, Takuyuki Katabami, Mika Tsuiki, Norio Wada, Yoshihiro Ogawa, Junji Kawashima, Masakatsu Sone, Takanobu Yoshimoto, Ryuji Okamoto, Megumi Fujita, Hiroki Kobayashi, Kouichi Tamura, Kohei Kamemura, Shintaro Okamura, Miki Kakutani, Akiyo Tanabe, Mitsuhide Naruse

    Clinical endocrinology   93 ( 3 )   229 - 237   2020.9

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    OBJECTIVE: Primary aldosteronism (PA) is considered a major cause of resistant hypertension (RHT). The prevalence of RHT has been recently reported to reach 18% in general hypertension. However, little is known about the prevalence and the outcomes after adrenalectomy of RHT in PA. Therefore, we aimed to clarify the prevalence and surgical outcomes in patients with both PA and RHT. PATIENTS AND DESIGN: Among 550 patients who underwent adrenalectomy for unilateral PA in the Japan PA Study, RHT was defined as an uncontrolled blood pressure (≥140/90 mm Hg) despite treatment with at least any three antihypertensives or hypertension controlled with at least four drugs. Surgical outcome was assessed by the biochemical and clinical outcome. RESULTS: Although 40 (7.3%) patients fulfilled the criteria for preoperative RHT, this should be underestimated because only 36% of patients with postoperative RHT were classified as having preoperative RHT. The prevalence of preoperative RHT was approximately 20% when estimated using the total number of patients with postoperative RHT and the ratio of postoperative RHT in patients with preoperative RHT. Although an improvement in hypertension was achieved in approximately 80% of patients with preoperative RHT, 20% of these exhibited persistent RHT. These patients were more obese than those for whom RHT improved after surgery. Notably, body mass index of ≥25 kg/m2 was an independent predictor of postoperative RHT. CONCLUSIONS: The prevalence of RHT in PA was lower than expected even with the adjustment for underestimation. Furthermore, obesity is an independent factor predicting the postoperative persistence of RHT.

    DOI: 10.1111/cen.14203

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  • Associations Between Changes in Plasma Renin Activity and Aldosterone Concentrations and Changes in Kidney Function After Treatment for Primary Aldosteronism. International journal

    Yusuke Kobayashi, Tatsuya Haze, Yuichiro Yano, Kouichi Tamura, Isao Kurihara, Takamasa Ichijo, Takashi Yoneda, Takuyuki Katabami, Mika Tsuiki, Norio Wada, Yoshihiro Ogawa, Junji Kawashima, Masakatsu Sone, Nobuya Inagaki, Tetsuya Yamada, Ryuji Okamoto, Megumi Fujita, Kohei Kamemura, Koichi Yamamoto, Shoichiro Izawa, Akiyo Tanabe, Mitsuhide Naruse

    Kidney international reports   5 ( 8 )   1291 - 1297   2020.8

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    INTRODUCTION: Greater reduction in estimated glomerular filtration rate (eGFR) after specific treatment for primary aldosteronism (PA) reflects improvement in glomerular hyperfiltration associated with PA and leads to better patient outcomes. However, little is known regarding the mechanisms underlying eGFR reduction after treatment for PA. METHODS: We analyzed data from the nationwide PA registry in Japan. Patients were assigned to adrenalectomy (n = 438) and mineralocorticoid receptor (MR) antagonist (n = 746) groups. We assessed associations between changes in blood pressure (BP), plasma renin activity (PRA) and plasma aldosterone concentrations (PAC), and eGFR before and 6 months after treatment for both groups. RESULTS: In a multivariable linear regression, the adjusted β values (95% confidence interval [CI]) for change in eGFR after treatment were -2.76 (-4.29, -1.22) ml/min per 1.73 m2 for PRA (per 3.2 ng/ml per hour), and 1.97 (1.08, 2.85) ml/min per 1.73 m2 for PAC (per 236.1 pg/ml) in the adrenalectomy group; and -0.45 (-0.89, -0.01) ml/min per 1.73 m2 for PRA and -0.72 (-1.62, 0.18) ml/min per 1.73 m2 for PAC in the MR antagonist group. Change in mean arterial pressure after treatment was not significantly associated with change in eGFR in either group. Changes in PRA and PAC but not BP before and 6 months after treatment for PA were associated with greater reductions in eGFR. CONCLUSION: Post-treatment improvements in glomerular hyperfiltration may be attributable to decreased MR activity in the kidneys, but not to reductions in systemic BP.

    DOI: 10.1016/j.ekir.2020.06.012

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  • Effect of cosyntropin during adrenal venous sampling on subtype of primary aldosteronism: analysis of surgical outcome. International journal

    Hiroki Kobayashi, Yoshihiro Nakamura, Masanori Abe, Isao Kurihara, Hiroshi Itoh, Takamasa Ichijo, Yoshiyu Takeda, Takashi Yoneda, Takuyuki Katabami, Mika Tsuiki, Norio Wada, Yoshihiro Ogawa, Ryuichi Sakamoto, Junji Kawashima, Masakatsu Sone, Nobuya Inagaki, Takanobu Yoshimoto, Tetsuya Yamada, Ryuji Okamoto, Yuichi Matsuda, Megumi Fujita, Minemori Watanabe, Kouichi Tamura, Akiyo Tanabe, Mitsuhide Naruse

    European journal of endocrinology   182 ( 3 )   265 - 273   2020.3

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    OBJECTIVES: We investigated the clinical significance of ACTH stimulation during adrenal venous sampling (AVS) by surgical outcome of primary aldosteronism (PA). DESIGN: Multicenter retrospective study by Japan PA study. METHOD: We allocated 314 patients with both basal and ACTH-stimulated AVS data who underwent adrenalectomy to three groups: basal lateralization index (LI) ≥2 with ACTH-stimulated LI ≥4 on the ipsilateral side (Unilateral (U) to U group, n = 245); basal LI <2 with ACTH-stimulated LI ≥4 (Bilateral (B) to U group, n = 15); and basal LI ≥2 with ACTH-stimulated LI <4 (U to B group, n = 54). We compared surgical outcomes among the groups using the Primary Aldosteronism Surgical Outcome (PASO) criteria. RESULTS: Compared with U to U group, U to B group had poor clinical and biochemical outcomes and low rates of adrenal adenoma as pathological findings (P = 0.044, 0.006, and 0.048, respectively), although there were no significant differences between U to U and B to U groups. All patients in U to B group with clinical and biochemical benefits, however, had adrenal adenoma as pathological findings and could be well differentiated from those with poor surgical outcomes via basal LI (>8.3), but not ACTH-stimulated LI. These results were similar even when we defined each group based on a cut-off value of 4 for basal LI. CONCLUSIONS: Although PA patients in U to B group had worse surgical outcomes than did those in U to U group, basal LI could discriminate among patients with better surgical outcomes in U to B group.

    DOI: 10.1530/EJE-19-0860

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  • Historical changes and between-facility differences in adrenal venous sampling for primary aldosteronism in Japan. International journal

    Yuichi Fujii, Yoshiyu Takeda, Isao Kurihara, Hiroshi Itoh, Takuyuki Katabami, Takamasa Ichijo, Norio Wada, Yui Shibayama, Takanobu Yoshimoto, Yoshihiro Ogawa, Junji Kawashima, Masakatsu Sone, Nobuya Inagaki, Katsutoshi Takahashi, Minemori Watanabe, Yuichi Matsuda, Hiroki Kobayashi, Hirotaka Shibata, Kohei Kamemura, Michio Otsuki, Koichi Yamamto, Atsushi Ogo, Toshihiko Yanase, Shintaro Okamura, Shozo Miyauchi, Megumi Fujita, Tomoko Suzuki, Hironobu Umakoshi, Tatsuki Ogasawara, Mika Tsuiki, Mitsuhide Naruse

    Journal of human hypertension   34 ( 1 )   34 - 42   2020.1

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    Primary aldosteronism (PA) is a common curable cause of hypertension. Adrenal venous sampling (AVS) is recommended for subtype diagnosis but is a difficult procedure. Recently, an increased prevalence of PA was reported, creating a greater demand for treatment of the condition in clinical facilities. The aim of the present study was to identify the historical changes over time and the differences between facilities in the success rate and subtype diagnosis of PA. The database of the PA registry developed by the Japan PA Study (JPAS) was used. A total of 2599 patients with PA who underwent AVS were evaluated. The overall success rate of AVS was 88%. The bilateral subtype was the dominant subtype, comprising 69% of cases. During the period 2004-2011 to 2011-2017, there were significant changes in the total number of AVS procedures (from 562 to 1732), ratio of ACTH administration with AVS (75 to 97%), success rate (79 to 90%), and proportion with bilateral subtype diagnosis (53 to 72%). There were also significant inter-facility differences in the number of AVS procedures (6 to 322), success rate (59 to 97%), and proportion with the bilateral subtype (44 to 86%). The principal enrolled department was Endocrinology (86%), and the ratio of unilateral PA was significantly higher in this department than in others (32% vs. 25%). In conclusion, the number of AVS procedures performed, the success rate, and the proportion with the bilateral subtype increased over time after normalizing the centre difference. Significant differences were observed between the centres.

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  • Predictors of Clinical Success After Surgery for Primary Aldosteronism in the Japanese Nationwide Cohort. International journal

    Mitsuha Morisaki, Isao Kurihara, Hiroshi Itoh, Mitsuhide Naruse, Yoshiyu Takeda, Takuyuki Katabami, Takamasa Ichijo, Norio Wada, Takanobu Yoshimoto, Yoshihiro Ogawa, Masakatsu Sone, Mika Tsuiki, Hirotaka Shibata, Junji Kawashima, Megumi Fujita, Minemori Watanabe, Yuichi Matsuda, Hiroki Kobayashi, Tomoko Suzuki

    Journal of the Endocrine Society   3 ( 11 )   2012 - 2022   2019.11

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    CONTEXT: Aldosterone-producing adenomas are a curable subtype of primary aldosteronism (PA); however, hypertension persists in some patients after adrenalectomy. OBJECTIVE: To identify factors associated with, and develop prediction models for, blood pressure (BP) normalization or improvement after adrenalectomy. DESIGN: Retrospective analysis of patients treated between 2006 and 2018, with a 6-month follow-up. SETTING: A nationwide, 29-center Japanese registry encompassing 15 university hospitals and 14 city hospitals. PATIENTS: We categorized 574 participants in the Japan Primary Aldosteronism Study, who were diagnosed with PA and underwent adrenalectomy, as BP normalized or improved, on the basis of their presentations at 6 months postsurgery. MAIN OUTCOME MEASURE: The rate of complete, partial, and absent clinical success. Predictive factors related to BP outcomes after PA surgery were also evaluated. RESULTS: Complete clinical success was achieved in 32.6% and partial clinical success was achieved in 53.0% of the patients at 6 months postsurgery. The following five variables were independent predictors for BP normalization: ≤7 years of hypertension, body mass index ≤25 kg/m2, no more than one antihypertensive medication, absence of medical history of diabetes, and female sex. The area under the receiver operator characteristic curve was 0.797 in the BP normalization model. CONCLUSION: We established models that predicted postoperative BP normalization in patients with PA. These should be useful for shared decision-making regarding adrenalectomy for PA.

    DOI: 10.1210/js.2019-00295

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  • Renal impairment is closely associated with plasma aldosterone concentration in patients with primary aldosteronism. International journal

    Akiyuki Kawashima, Masakatsu Sone, Nobuya Inagaki, Yoshiyu Takeda, Hiroshi Itoh, Isao Kurihara, Hironobu Umakoshi, Takamasa Ichijo, Takuyuki Katabami, Norio Wada, Yoshihiro Ogawa, Junji Kawashima, Megumi Fujita, Shozo Miyauchi, Shintaro Okamura, Tomikazu Fukuoka, Toshihiko Yanase, Shoichiro Izawa, Yuichiro Yoshikawa, Shigeatsu Hashimoto, Masanobu Yamada, Tatsuya Kai, Tomoko Suzuki, Mitsuhide Naruse

    European journal of endocrinology   181 ( 3 )   339 - 350   2019.9

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    OBJECTIVE: Several clinical studies have reported that renal impairments are sometimes observed in patients with primary aldosteronism (PA). We analyzed the prevalence of renal impairments in PA patients and identified parameters that increase the risk for them. DESIGN: This is a retrospective cross-sectional study. We assessed the PA database established by the multicenter Japan PA study (JPAS). Data were also collected from patients with essential hypertension (EHT). METHODS: We compared the prevalences of proteinuria and lowered estimated glomerular filtration rate (eGFR) between patients with PA and age, sex, blood pressure and duration of hypertension-matched patients with EHT. We also performed logistic regression analysis to identify parameters that increase the risk for these renal impairments. RESULTS: Among 2366 PA patients, the prevalences of proteinuria and lowered eGFR were 10.3 and 11.6%, respectively. The prevalence of proteinuria was significantly higher in PA patients than matched-EHT patients (16.8 vs 4.4%), whereas there was no significant difference in the prevalence of lowered eGFR (17.2 vs 15.0%). The logistic regression analysis also showed that the plasma aldosterone concentration (PAC) significantly increases the risk of proteinuria and lowered eGFR, independent of other known risk factors. CONCLUSION: Plasma aldosterone levels are closely associated with renal impairment in patients with PA. This is contrast to our earlier finding that the PAC was not itself linearly associated with cardiovascular events such as stroke or ischemic heart disease. The mechanism underlying the kidney damage in patients with PA may differ from that affecting the cardiovascular system.

    DOI: 10.1530/EJE-19-0047

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  • Association Between Acute Fall in Estimated Glomerular Filtration Rate After Treatment for Primary Aldosteronism and Long-Term Decline in Renal Function. International journal

    Hiroki Kobayashi, Masanori Abe, Yoshihiro Nakamura, Katsutoshi Takahashi, Megumi Fujita, Yoshiyu Takeda, Takashi Yoneda, Isao Kurihara, Hiroshi Itoh, Mika Tsuiki, Norio Wada, Takamasa Ichijo, Takuyuki Katabami, Yoshihiro Ogawa, Junji Kawashima, Takanobu Yoshimoto, Masakatsu Sone, Nobuya Inagaki, Minemori Watanabe, Kohei Kamemura, Yuichi Matsuda, Shoichiro Izawa, Makito Tanabe, Akiyo Tanabe, Tomoko Suzuki, Mitsuhide Naruse

    Hypertension (Dallas, Tex. : 1979)   74 ( 3 )   630 - 638   2019.9

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    Primary aldosteronism causes renal structural damage after glomerular hyperfiltration, and primary aldosteronism-specific treatment leads to an acute fall in estimated glomerular filtration rate (eGFR). We investigated whether this change affected the long-term eGFR slope in a retrospective cohort from the multicenter Japan Primary Aldosteronism Study. We allocated patients with primary aldosteronism to the adrenalectomy (n=202) and MR (mineralocorticoid receptor) antagonist (n=303) groups based on their treatment history and analyzed the association between the initial eGFR fall and long-term eGFR slope. The increased age, low serum potassium levels, high eGFR, and high plasma aldosterone levels were independent predictors for a large initial eGFR fall in both groups. Our analysis of tertiles based on the initial eGFR fall revealed that in the MR antagonist group, patients with a small initial eGFR fall had a significantly steeper long-term eGFR slope than those with a large initial fall (tertile 1 versus 2, P=0.025; tertile 1 versus 3, P=0.017). These associations were not identified in the adrenalectomy group. Thus, the smaller the acute fall in eGFR by initiation of MR antagonists, the greater was the rate of long-term eGFR decline. While the acute fall in eGFR induced by primary aldosteronism-specific treatment is occasionally a clinical concern, our findings highlight the favorable implications of the acute fall with respect to long-term renal outcomes.

    DOI: 10.1161/HYPERTENSIONAHA.119.13131

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  • Effectiveness and safety of cinacalcet for primary hyperparathyroidism: a single center experience.

    Katsunori Manaka, Junichiro Sato, Yuka Kinoshita, Nobuaki Ito, Megumi Fujita, Taroh Iiri, Masaomi Nangaku, Noriko Makita

    Endocrine journal   66 ( 8 )   683 - 689   2019.8

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    Primary hyperparathyroidism (PHPT) is a common endocrine disease. Although surgical treatment is curative in most cases, there are few alternative therapies for the hypercalcemia caused by PHPT. Cinacalcet is a positive allosteric modulator of the calcium sensing receptor and was conditionally approved in Japan in 2014 to treat PHPT cases. However, there have been few reports on the outcomes. In our present study, we investigated the efficacy and safety of cinacalcet in 61 PHPT patients who were treated with this agent at our hospital between January 2014 and March 2017. The corrected serum Ca and intact PTH levels were significantly reduced by this treatment, whereas the serum phosphorus levels significantly increased. There were no significant differences in the eGFR or urinary Ca to urinary creatinine ratio between baseline and the maintenance phase. In terms of bone mineral density, there were significant increases observed in the 16 cases for whom a baseline value was available, 11 of whom had been treated for osteoporosis. The most common adverse events from cinacalcet treatment were gastrointestinal symptom, such as nausea and appetite loss. Other adverse events included severe dehydration due to hypercalcemia, myalgia, hypocalcemia, and increased urinary calcium excretion. Seven patients were switched to surgical treatment, and the drug was discontinued in 9 other patients, due to adverse effects. Our present study findings demonstrate that cinacalcet is an effective therapeutic option for PHPT from the perspective of hypercalcemia improvement but that adverse gastrointestinal effects of this drug occur at a frequency of about 10%.

    DOI: 10.1507/endocrj.EJ19-0034

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  • Sex Difference in the Association Between Subtype Distribution and Age at Diagnosis in Patients With Primary Aldosteronism. International journal

    Hiroshi Akasaka, Koichi Yamamoto, Hiromi Rakugi, Motonori Nagasawa, Ryo Nakamaru, Takamasa Ichijo, Yoshiyu Takeda, Isao Kurihara, Takuyuki Katabami, Mika Tsuiki, Norio Wada, Yoshihiro Ogawa, Junji Kawashima, Masakatsu Sone, Kohei Kamemura, Takanobu Yoshimoto, Yuichi Matsuda, Megumi Fujita, Hiroki Kobayashi, Minemori Watanabe, Kouichi Tamura, Shintaro Okamura, Shozo Miyauchi, Shoichiro Izawa, Yoshiro Chiba, Akiyo Tanabe, Mitsuhide Naruse

    Hypertension (Dallas, Tex. : 1979)   74 ( 2 )   368 - 374   2019.8

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    Primary aldosteronism (PA) is the most frequent cause of secondary hypertension. Adrenal vein sampling (AVS) is an established method for finding patients with the unilateral subtype of PA, for which adrenalectomy is an applicable treatment. In this study, we analyzed a large database of patients with PA who underwent adrenal vein sampling, to investigate the sex differences in the impact of age at diagnosis on the subtype and cause of PA. In 2122 patients, women with the unilateral subtype were younger than men with the same subtype and women with the bilateral subtype. Younger age and older age were associated with unilateral PA in women and men, respectively. After stratification by tertiles of age, there was a trend of decreased and increased incidence of unilateral PA with aging in women and men, respectively. Male sex was a predictor of unilateral PA in middle-aged and older patients but not in younger patients. We also found that obesity, a known factor associated with idiopathic hyperaldosteronism, was positively associated with bilateral PA in younger patients but not in older patients. These findings suggest that the proportion of operable patients with unilateral PA differs depending on the combination of sex and age, and that other than obesity, the cause of PA is also associated with the bilateral subtype in older patients.

    DOI: 10.1161/HYPERTENSIONAHA.119.13006

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  • Lateralizing Asymmetry of Adrenal Imaging and Adrenal Vein Sampling in Patients With Primary Aldosteronism. International journal

    Norio Wada, Yui Shibayama, Takashi Yoneda, Takuyuki Katabami, Isao Kurihara, Mika Tsuiki, Takamasa Ichijo, Yoshihiro Ogawa, Junji Kawashima, Masakatsu Sone, Takanobu Yoshimoto, Yuichi Matsuda, Megumi Fujita, Hiroki Kobayashi, Kouichi Tamura, Kohei Kamemura, Michio Otsuki, Shintaro Okamura, Mitsuhide Naruse

    Journal of the Endocrine Society   3 ( 7 )   1393 - 1402   2019.7

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    CONTEXT: In patients with primary aldosteronism (PA), it remains unclear whether aldosterone-producing adenomas are likely to develop in the left or right adrenal gland. OBJECTIVE: To investigate left-right differences of PA laterality diagnoses via CT imaging and adrenal vein sampling (AVS). DESIGN: Retrospective, observational study. PATIENTS: From the Japan Primary Aldosteronism Study, 1493 patients with PA were enrolled who underwent CT and ACTH-stimulated AVS. MEASUREMENTS: Left or right adrenal nodular lesion distribution and laterality observed on CT scans and from AVS were noted. RESULTS: Both on CT scans and AVS, unilateral results were observed more frequently on the left side than on the right side (25.1% vs 15.4% and 17.3% vs 13.5%, respectively; P < 0.01for both diagnostic techniques). There was no significant difference in the concordance rate for CT and AVS between patients with left and right unilateral nodular lesions observed on CT scans (44.1% and 50.9%, respectively; P = 0.15). In patients with nodules <20 mm, the concordance rate was significantly greater on the right side than the left side (45.8% vs 56.4%; P = 0.03). In patients with bilateral results of AVS, unilateral nodular lesions were detected more frequently on the left side than the right side (17.8% vs 9.4%; P < 0.01). CONCLUSION: These results suggest aldosterone-producing adenomas and nonfunctioning tumors are more likely to develop on the left side in patients with PA and that misdiagnosis of CT-based lateralization may occur more frequently on the left side.

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  • Clinical and biochemical outcomes after adrenalectomy and medical treatment in patients with unilateral primary aldosteronism. International journal

    Takuyuki Katabami, Hisashi Fukuda, Hidekazu Tsukiyama, Yasushi Tanaka, Yoshiyu Takeda, Isao Kurihara, Hiroshi Ito, Mika Tsuiki, Takamasa Ichijo, Norio Wada, Yui Shibayama, Takanobu Yoshimoto, Yoshihiro Ogawa, Junji Kawashima, Masakatsu Sone, Nobuya Inagaki, Katsutoshi Takahashi, Megumi Fujita, Minemori Watanabe, Yuichi Matsuda, Hiroki Kobayashi, Hirotaka Shibata, Kohei Kamemura, Michio Otsuki, Yuichi Fujii, Koichi Yamamoto, Atsushi Ogo, Toshihiko Yanase, Tomoko Suzuki, Mitsuhide Naruse

    Journal of hypertension   37 ( 7 )   1513 - 1520   2019.7

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    OBJECTIVES: Current clinical guidelines of primary aldosteronism recommend adrenalectomy (AdX) for unilateral primary aldosteronism based on the studies showing the potential superiority of AdX over the medical treatment. However, since most medically treated cases consisted of bilateral primary aldosteronism and all surgically treated cases consisted of unilateral primary aldosteronism, the different subtype of primary aldosteronism could be a bias for their effects. This study compared the effects of AdX and medical therapy in patients with unilateral primary aldosteronism confirmed by adrenal vein sampling. METHODS: Of the 339 patients with unilateral primary aldosteronism in the Japan Primary Pldosteronism Study data base, unilateral AdX and treatment with mineral corticoid receptor antagonists (MRAs) was done in 276 patients (AdX group) and in 63 patients (MRAs group), respectively. The effects were compared by the clinical (improvement of blood pressure) and biochemical outcomes (improvement of hypokalemia). RESULTS: At baseline, use of potassium replacement, plasma aldosterone concentration, aldosterone-to-renin ratio, estimated glomerular filtration rate, and prevalence of adrenal mass on imaging were higher in the AdX group than in the MRAs group. At 6 months after commencement of specific treatment for primary aldosteronism, clinical outcome and biochemical outcome in the AdX group were superior than those in the MRAs group. The difference of the outcome between the two groups were the case even after adjusting for the different clinical backgrounds in the two groups before the specific treatment. CONCLUSION: Our study provides evidence that AdX is the first choice of treatment in the patients with unilateral primary aldosteronism in terms of clinical and biochemical outcome.

    DOI: 10.1097/HJH.0000000000002070

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  • Influence of antihypertensive drugs in the subtype diagnosis of primary aldosteronism by adrenal venous sampling. International journal

    Motonori Nagasawa, Koichi Yamamoto, Hiromi Rakugi, Masao Takeda, Hiroshi Akasaka, Hironobu Umakoshi, Mika Tsuiki, Yoshiyu Takeda, Isao Kurihara, Hiroshi Itoh, Takamasa Ichijo, Takuyuki Katabami, Norio Wada, Yui Shibayama, Takanobu Yoshimoto, Yoshihiro Ogawa, Junji Kawashima, Masakatsu Sone, Nobuya Inagaki, Katsutoshi Takahashi, Megumi Fujita, Minemori Watanabe, Yuichi Matsuda, Hiroki Kobayashi, Hirotaka Shibata, Kohei Kamemura, Michio Otsuki, Yuichi Fujii, Atsushi Ogo, Shintaro Okamura, Shozo Miyauchi, Toshihiko Yanase, Tomoko Suzuki, Takashi Kawamura, Mitsuhide Naruse

    Journal of hypertension   37 ( 7 )   1493 - 1499   2019.7

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    OBJECTIVES: Because of the influence on the renin-angiotensin-aldosterone system, it is recommended to avoid, if possible, the use of angiotensin-converting-enzyme inhibitors, angiotensin II type 1 receptor blockers, diuretics, β-blockers, and mineralocorticoid receptor antagonists during the diagnostic period of primary aldosteronism. A laterality index more than 4 in adrenocorticotropic hormone (ACTH)-stimulated adrenal venous sampling (ACTH-AVS) is a widely used classification of the unilateral subtype that can benefit from adrenalectomy. Here, we revealed clinical features of patients taking drugs that could affect the primary aldosteronism diagnosis (DAPD) and investigated whether the classification with laterality index more than 4 in ACTH-AVS is applicable to these patients. PATIENTS AND METHODS: Using a large database of primary aldosteronism patients in Japan, we analyzed 2122 patients with successful ACTH-AVS. RESULTS: Patients who received any DAPD (n = 209) showed higher prevalence of comorbidity burdens and took more antihypertensive drugs compared with patients without DAPD. In patients taking DAPD, those with laterality index more than 4 had a higher prevalence of hypokalemia, a higher aldosterone-to-renin ratio and a higher prevalence of adrenal mass than those with laterality index of 4 or less. Adrenalectomy was performed in 76% patients with laterality index more than 4 and 20% with laterality index of 4 or less. Patients who underwent adrenalectomy showed biochemical cure in 89% with laterality index more than 4 and 50% with laterality index of 4 or less (P = 0.001). Multivariate regression analysis showed that laterality index more than 4 was an independent predictor of a biochemical cure. Biochemical cure rate in patients with laterality index more than 4 was consistently high, irrespective of the potential effect of individual DAPD on laterality index. CONCLUSION: Our findings suggest that in primary aldosteronism patients to whom DAPD were administrated due to severe clinical features, laterality index more than 4 in ACTH-AVS could accurately predict a biochemical cure after adrenalectomy.

    DOI: 10.1097/HJH.0000000000002047

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  • High Prevalence of Diabetes in Patients With Primary Aldosteronism (PA) Associated With Subclinical Hypercortisolism and Prediabetes More Prevalent in Bilateral Than Unilateral PA: A Large, Multicenter Cohort Study in Japan. International journal

    Yuko Akehi, Toshihiko Yanase, Ryoko Motonaga, Hironobu Umakoshi, Mika Tsuiki, Yoshiyu Takeda, Takashi Yoneda, Isao Kurihara, Hiroshi Itoh, Takuyuki Katabami, Takamasa Ichijo, Norio Wada, Yui Shibayama, Takanobu Yoshimoto, Kenji Ashida, Yoshihiro Ogawa, Junji Kawashima, Masakatsu Sone, Nobuya Inagaki, Katsutoshi Takahashi, Megumi Fujita, Minemori Watanabe, Yuichi Matsuda, Hiroki Kobayashi, Hirotaka Shibata, Kohei Kamemura, Michio Otsuki, Yuichi Fujii, Koichi Yamamoto, Atsushi Ogo, Shintaro Okamura, Shozo Miyauchi, Tomikazu Fukuoka, Shoichiro Izawa, Shigeatsu Hashimoto, Masanobu Yamada, Yuichiro Yoshikawa, Tatsuya Kai, Tomoko Suzuki, Takashi Kawamura, Mitsuhide Naruse

    Diabetes care   42 ( 5 )   938 - 945   2019.5

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    OBJECTIVE: To investigate the prevalence and causes of diabetes in patients with primary aldosteronism (PA) in a multi-institutional cohort study in Japan. RESEARCH DESIGN AND METHODS: The prevalence of diabetes was determined in 2,210 patients with PA (diagnosed or glycated hemoglobin [HbA1c] ≥6.5% [≥48 mmol/mol]; NGSP) and compared with that of the Japanese general population according to age and sex. In 1,386 patients with PA and clear laterality (unilateral or bilateral), the effects of plasma aldosterone concentration (PAC), hypokalemia (<3.5 mEq/L), suspected subclinical hypercortisolism (SH; serum cortisol ≥1.8 µg/dL after 1-mg dexamethasone suppression test), and PA laterality on the prevalence of diabetes or prediabetes (5.7% ≤ HbA1c <6.5% [39 mmol/mol ≤ HbA1c <48 mmol/mol]) were examined. RESULTS: Of the 2,210 patients with PA, 477 (21.6%) had diabetes. This prevalence is higher than that in the general population (12.1%) or in 10-year cohorts aged 30-69 years. Logistic regression or χ2 test revealed a significant contribution of suspected SH to diabetes. Despite more active PA profiles (e.g., higher PAC and lower potassium concentrations) in unilateral than bilateral PA, BMI and HbA1c values were significantly higher in bilateral PA. PA laterality had no effect on the prevalence of diabetes; however, the prevalence of prediabetes was significantly higher in bilateral than unilateral PA. CONCLUSIONS: Individuals with PA have a high prevalence of diabetes, which is associated mainly with SH. The prevalence of prediabetes is greater for bilateral than unilateral PA, suggesting a unique metabolic cause of bilateral PA.

    DOI: 10.2337/dc18-1293

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  • Reducing the gender gap in academic activities: a 10-year progress report by the Japan Endocrine Society Women Endocrinologists Association (JES-We-Can).

    Miyuki Katai, Kanako Sakurai, Megumi Fujita, Mayumi Yamamoto, Mari Hotta Suzuki

    Endocrine journal   66 ( 4 )   359 - 368   2019.4

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    The Japan Endocrine Society (JES) has the largest ratio of female membership among societies associated with Internal Medicine in Japan; half of female members are in their 20s or 30s at present. In 2009, JES organized the "JES-We-Can" committee to promote women's career development. To evaluate the effectiveness of JES-We-Can, we investigated the gender balance of various activities at JES in fiscal 2009 and 2017. Significant gender-differences were not observed in the acquisition rate of board-certified endocrinologists (BCEs) aged <40 y in 2009 and 2017. However, the acquisition rate of BCEs among women aged ≥40 y was significantly lower than men in 2009. In 2017, the gender-difference among BCEs in this group (currently aged ≥50 y) has considerably improved, but is not resolved. The acquisition rate of certificated endocrine educators (CEEs) among women was still significantly lower than men at all ages in 2017. Since the ratio of women oral speakers or poster presenters at annual academic meetings have grown to equal or surpass the membership ratio, female members make efficient contributions to JES. The numbers of women chairpersons, symposiasts, lecturers and invited speakers have increased, but remain limited. JES-We-Can was found to be effective in reducing the gender gap in academic activities at JES, but JES-We-Can should support women more intensely to raise the rate of CEEs among all ages and BCEs currently over 50 y, and to promote more women into higher positions in JES in the future. These actions are expected to introduce new and diverse perspectives into academia.

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  • Clinical Characteristics and Postoperative Outcomes of Primary Aldosteronism in the Elderly. International journal

    Masao Takeda, Koichi Yamamoto, Hiroshi Akasaka, Hiromi Rakugi, Mitsuhide Naruse, Yoshiyu Takeda, Isao Kurihara, Hiroshi Itoh, Hironobu Umakoshi, Mika Tsuiki, Takamasa Ichijo, Takuyuki Katabami, Norio Wada, Yui Shibayama, Takanobu Yoshimoto, Yoshihiro Ogawa, Junji Kawashima, Masakatsu Sone, Nobuya Inagaki, Katsutoshi Takahashi, Megumi Fujita, Minemori Watanabe, Yuichi Matsuda, Hiroki Kobayashi, Hirotaka Shibata, Kohei Kamemura, Michio Otsuki, Yuichi Fujii, Atsushi Ogo, Shintaro Okamura, Shozo Miyauchi, Toshihiko Yanase, Tomoko Suzuki, Takashi Kawamura

    The Journal of clinical endocrinology and metabolism   103 ( 10 )   3620 - 3629   2018.10

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    CONTEXT: Primary aldosteronism (PA) in the elderly has increased in importance in association with population aging. OBJECTIVE: To investigate the characteristics and outcomes of elderly patients with PA undergoing adrenalectomy. PATIENTS AND METHODS: Using a database of patients with PA who underwent adrenal venous sampling (AVS), we compared elderly patients (≥65 years old) with nonelderly patients (<65 years old) in terms of characteristics, subtype classification in ACTH-stimulated AVS, and outcomes after adrenalectomy. RESULTS: The elderly group had a higher prevalence of comorbidities than the nonelderly group. The proportion of the unilateral subtype [defined as a lateralization index (LI) >4] was comparable between the age groups. In patients who received adrenalectomy, biochemical cure was comparable between the groups, whereas persistent hypertension was more common in the elderly group. The prevalences of hyperkalemia and renal impairment (chronic kidney disease stage 3b or higher) were higher in the elderly group. Multiple regression analysis showed that the duration of hypertension predicted persistent hypertension and hyperkalemia and that preoperative estimated glomerular filtration rate predicted renal impairment in the elderly group. LI >4 in AVS was an independent predictor of biochemical cure after adrenalectomy in the elderly group but not in the nonelderly group. Age was negatively associated with biochemical cure in patients with LI ≤4. CONCLUSION: Adrenalectomy contributes to biochemical improvement in elderly patients if determined in accordance with AVS. The treatment strategy should be determined considering the high postoperative incidence of persistent hypertension and hyperkalemia in elderly patients with a long history of hypertension or renal impairment in those with reduced renal function.

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  • The Occurrence of Apparent Bilateral Aldosterone Suppression in Adrenal Vein Sampling for Primary Aldosteronism. International journal

    Yui Shibayama, Norio Wada, Mitsuhide Naruse, Isao Kurihara, Hiroshi Ito, Takashi Yoneda, Yoshiyu Takeda, Hironobu Umakoshi, Mika Tsuiki, Takamasa Ichijo, Hisashi Fukuda, Takuyuki Katabami, Takanobu Yoshimoto, Yoshihiro Ogawa, Junji Kawashima, Yuichi Ohno, Masakatsu Sone, Megumi Fujita, Katsutoshi Takahashi, Hirotaka Shibata, Kohei Kamemura, Yuichi Fujii, Koichi Yamamoto, Tomoko Suzuki

    Journal of the Endocrine Society   2 ( 5 )   398 - 407   2018.5

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    CONTEXT: In adrenal venous sampling (AVS) for patients with primary aldosteronism (PA), apparent bilateral aldosterone suppression (ABAS), defined as lower aldosterone/cortisol ratios in the bilateral adrenal veins than that in the inferior vena cava, is occasionally experienced. ABAS is uninterpretable with respect to lateralization of excess aldosterone production. We previously reported that ABAS was not a rare phenomenon and was significantly reduced after adrenocorticotropic hormone (ACTH) administration. OBJECTIVE: To validate the effects of ACTH administration and adding sampling positions in the left adrenal vein on the prevalence of ABAS in the larger Japan Primary Aldosteronism Study. PATIENTS: The data from 1689 patients with PA who underwent AVS between January 2006 and October 2016 were studied. All patients in the previous study, the West Japan Adrenal Vein Sampling study, were excluded. OUTCOME MEASUREMENTS: The prevalence of ABAS was investigated at two sampling positions in the left adrenal vein, the central vein and the common trunk, without and with ACTH administration. RESULTS: The prevalence of ABAS with ACTH administration was significantly lower than that without ACTH administration [without ACTH vs with ACTH: 79/440 (18.0%) vs 45/591 (7.6%); P < 0.001]. With ACTH administration, the prevalence of ABAS was not different between the sampling position, at the central vein and at the common trunk [33/591 (5.6%) vs 32/591 (5.4%); P = 1.00]. CONCLUSIONS: The effectiveness of ACTH administration for the reduction of ABAS in AVS regardless of the sampling position in the left adrenal vein was confirmed in the larger cohort.

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  • Prevalence of Cardiovascular Disease and Its Risk Factors in Primary Aldosteronism: A Multicenter Study in Japan. International journal

    Youichi Ohno, Masakatsu Sone, Nobuya Inagaki, Toshinari Yamasaki, Osamu Ogawa, Yoshiyu Takeda, Isao Kurihara, Hiroshi Itoh, Hironobu Umakoshi, Mika Tsuiki, Takamasa Ichijo, Takuyuki Katabami, Yasushi Tanaka, Norio Wada, Yui Shibayama, Takanobu Yoshimoto, Yoshihiro Ogawa, Junji Kawashima, Katsutoshi Takahashi, Megumi Fujita, Minemori Watanabe, Yuichi Matsuda, Hiroki Kobayashi, Hirotaka Shibata, Kohei Kamemura, Michio Otsuki, Yuichi Fujii, Koichi Yamamoto, Atsushi Ogo, Shintaro Okamura, Shozo Miyauchi, Tomikazu Fukuoka, Shoichiro Izawa, Takashi Yoneda, Shigeatsu Hashimoto, Toshihiko Yanase, Tomoko Suzuki, Takashi Kawamura, Yasuharu Tabara, Fumihiko Matsuda, Mitsuhide Naruse

    Hypertension (Dallas, Tex. : 1979)   71 ( 3 )   530 - 537   2018.3

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    There have been several clinical studies examining the factors associated with cardiovascular disease (CVD) in patients with primary aldosteronism (PA); however, their results have left it unclear whether CVD is affected by the plasma aldosterone concentration or hypokalemia. We assessed the PA database established by the multicenter JPAS (Japan Primary Aldosteronism Study) and compared the prevalence of CVD among patients with PA with that among age-, sex-, and blood pressure-matched essential hypertension patients and participants with hypertension in a general population cohort. We also performed binary logistic regression analysis to determine which parameters significantly increased the odds ratio for CVD. Of the 2582 patients with PA studied, the prevalence of CVD, including stroke (cerebral infarction, cerebral hemorrhage, or subarachnoid hemorrhage), ischemic heart disease (myocardial infarction or angina pectoris), and heart failure, was 9.4% (stroke, 7.4%; ischemic heart disease, 2.1%; and heart failure, 0.6%). The prevalence of CVD, especially stroke, was higher among the patients with PA than those with essential hypertension/hypertension. Hypokalemia (K+ ≤3.5 mEq/L) and the unilateral subtype significantly increased adjusted odds ratios for CVD. Although aldosterone levels were not linearly related to the adjusted odds ratio for CVD, patients with plasma aldosterone concentrations ≥125 pg/mL had significantly higher adjusted odds ratios for CVD than those with plasma aldosterone concentrations <125 pg/mL. Thus, patients with PA seem to be at a higher risk of developing CVD than patients with essential hypertension. Moreover, patients with PA presenting with hypokalemia, the unilateral subtype, or plasma aldosterone concentration ≥125 pg/mL are at a greater risk of CVD and have a greater need for PA-specific treatments than others.

    DOI: 10.1161/HYPERTENSIONAHA.117.10263

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  • Mineralocorticoid receptor--Rac1 activation and oxidative stress play major roles in salt-induced hypertension and kidney injury in prepubertal rats. International journal

    Hiroo Kawarazaki, Katsuyuki Ando, Shigeru Shibata, Kazuhiko Muraoka, Megumi Fujita, Chiaki Kawarasaki, Toshiro Fujita

    Journal of hypertension   30 ( 10 )   1977 - 85   2012.10

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    OBJECTIVES: To elucidate the roles that renal mineralocorticoid receptor-Rac1 interactions and oxidative stress play in salt-induced hypertension and renal injury in prepubertal rats. METHODS: Three-week-old male Sprague Dawley rats were uninephrectomized (UNx) and fed a high-salt (8% NaCl) diet for 4 weeks. Five were left untreated, whereas the remaining rats were administered an mineralocorticoid receptor blocker (n = 5), a Rac1 inhibitor (n = 5), a Rho-kinase inhibitor (n = 5), or the superoxide dismutase mimetic tempol (n = 5). A control group of young UNx rats (n = 5) was fed a normal-salt (0.5% NaCl) diet. The rats were sacrificed after a 4-week experimental period. Blood pressure, urinary protein, histological morphology, and renal serum-regulated and glucocorticoid-regulated kinase (Sgk) 1 and Rac1 expression were evaluated. The effect of adrenalectomy with dexamethasone supplementation in young salt-loaded UNx rats (n = 5) was also evaluated. RESULTS: Excessive salt intake induced hypertension and proteinuria in the young UNx rats, whose kidneys showed marked histological injury, Sgk1 overexpression and Rac1 activation. Both mineralocorticoid receptor blockade and Rac1 inhibition markedly prevented these abnormalities associated with a reduction in renal Rac1 expression. Adrenalectomy, but not Rho-kinase inhibition, also prevented salt-induced renal injury. Interestingly, tempol inhibited renal Rac1 activation and renal injury. CONCLUSIONS: These findings suggest that Rac1-related mineralocorticoid receptor activation contributed to salt-induced hypertension and kidney injury in young UNx rats. Furthermore, as adrenalectomy abrogated salt-induced proteinuria, Rac1 may be an enhancer of aldosterone-induced mineralocorticoid receptor activation. Oxidative stress may also modify the interaction between Rac1 and mineralocorticoid receptor.

    DOI: 10.1097/HJH.0b013e3283576904

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  • Mineralocorticoid receptor activation: a major contributor to salt-induced renal injury and hypertension in young rats. International journal

    Hiroo Kawarazaki, Katsuyuki Ando, Megumi Fujita, Hiromitsu Matsui, Ai Nagae, Kazuhiko Muraoka, Chiaki Kawarasaki, Toshiro Fujita

    American journal of physiology. Renal physiology   300 ( 6 )   F1402-9   2011.6

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    Excessive salt intake is known to preferentially increase blood pressure (BP) and promote kidney damage in young, salt-sensitive hypertensive human and animal models. We have suggested that mineralocorticoid receptor (MR) activation plays a major role in kidney injury in young rats. BP and urinary protein were compared in young (3-wk-old) and adult (10-wk-old) uninephrectomized (UNx) Sprague-Dawley rats fed a high (8.0%)-salt diet for 4 wk. The effects of the MR blocker eplerenone on BP and renal injury were examined in the high-salt diet-fed young UNx rats. Renal expression of renin-angiotensin-aldosterone (RAA) system components and of inflammatory and oxidative stress markers was also measured. The effects of the angiotensin receptor blocker olmesartan with or without low-dose aldosterone infusion, the aldosterone synthase inhibitor FAD286, and the antioxidant tempol were also studied. Excessive salt intake induced greater hypertension and proteinuria in young rats than in adult rats. The kidneys of young salt-loaded rats showed marked histological injury, overexpression of RAA system components, and an increase in inflammatory and oxidative stress markers. These changes were markedly ameliorated by eplerenone treatment. Olmesartan also ameliorated salt-induced renal injury but failed to do so when combined with low-dose aldosterone infusion. FAD286 and tempol also markedly reduced urinary protein. UNx rats exposed to excessive salt at a young age showed severe hypertension and renal injury, likely primarily due to MR activation and secondarily due to angiotensin receptor activation, which may be mediated by inflammation and oxidative stress.

    DOI: 10.1152/ajprenal.00691.2010

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  • Mineralocorticoid receptor activation contributes to salt-induced hypertension and renal injury in prepubertal Dahl salt-sensitive rats. International journal

    Hiroo Kawarazaki, Katsuyuki Ando, Ai Nagae, Megumi Fujita, Hiromitsu Matsui, Toshiro Fujita

    Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association   25 ( 9 )   2879 - 89   2010.9

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    BACKGROUND: Excessive prepubertal salt intake permanently increases blood pressure (BP). We examined the role that the mineralocorticoid receptor (MR) plays in the salt-induced hypertension and renal damage of prepubertal Dahl salt-sensitive (SS) rats. METHODS: Prepubertal (6 weeks old) and adult (10 weeks old) Dahl SS rats fed a high (8.0%) salt (HS) diet for 10 weeks were compared in terms of BP and renal function. The effect of treatment between the ages of 4 and 10 weeks with the MR antagonist eplerenone (0.125% in chow), the vasodilator hydralazine (50 mg/kg/day in drinking water) or the superoxide dismutase mimetic 4-hydroxy-2,2,6,6-tetramethyl-piperidine-N-oxyl (tempol) (0.6 mmol/kg/day in drinking water) on the BP and renal function of prepubertal rats fed a HS diet for 10 weeks was also examined. RESULTS: Excessive salt intake starting in prepuberty was associated with a higher BP increase and greater proteinuria than if it started in adulthood. Eplerenone moderately reduced BP and markedly improved renal injury during its administration in prepubertal rats. These effects continued after drug discontinuation. Hydralazine greatly decreased BP and reduced proteinuria, but these effects were completely lost after drug discontinuation. Excessive salt increased urinary 8-hydroxy-2'-deoxyguanosine levels, intrarenal macrophage infiltration and renal plasminogen activator inhibitor-1 and transforming growth factor-beta mRNA expression. Eplerenone, but not hydralazine, attenuated these salt-induced inflammatory reactions. Tempol improved salt-induced hypertension and renal injury, even after its discontinuation. CONCLUSIONS: Dahl SS rats exposed to excessive salt in prepubescence show a permanent increase in susceptibility to salt-induced hypertension and proteinuria. MR activation may promote these effects at least in part by inducing oxidation and inflammation.

    DOI: 10.1093/ndt/gfq197

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  • Protective effect of dietary potassium against cardiovascular damage in salt-sensitive hypertension: possible role of its antioxidant action. International journal

    Katsuyuki Ando, Hiromitsu Matsui, Megumi Fujita, Toshiro Fujita

    Current vascular pharmacology   8 ( 1 )   59 - 63   2010.1

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    It is well known that high salt intake induces hypertension and cardiovascular damage, while dietary potassium supplementation counteracts these harmful effects. Actually, the protective effect of potassium is strengthened with excess salt as compared with salt depletion. Although the precise mechanisms have not been fully elucidated, in our previous reports, the antihypertensive effect of dietary potassium was accompanied by sympathetic nerve inhibition in salt-sensitive hypertension. Also, potassium supplement suppressed salt-induced insulin resistance. These effects of dietary potassium can explain its cardio- and vasculo-protective action in addition to the potassium supplementation induced decreased salt-induced rise in blood pressure. On the other hand, salt-sensitive hypertension is associated with reactive oxygen species (ROS) overproduction. Moreover, sympathoexcitation can be induced by central ROS upregulation and insulin resistance can be caused by ROS excess in the target organs of insulin, such as skeletal muscle. Conversely, the seemingly different actions of potassium can be explained by the antioxidant effect of dietary potassium; in our recent studies, potassium supplementation inhibits salt-induced progress of cardiac diastolic dysfunction and vascular neointima formation by cuff placement around arteries, associated with the inhibition of regional ROS overproduction, in salt-sensitive hypertension. Thus, it is possible that dietary potassium protects against salt-induced cardiovascular damage by the reduction of ROS generation and by central sympatholytic action and amelioration of insulin resistance induced through its antioxidant effect.

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  • Salt excess causes left ventricular diastolic dysfunction in rats with metabolic disorder. International journal

    Hiromitsu Matsui, Katsuyuki Ando, Hiroo Kawarazaki, Ai Nagae, Megumi Fujita, Tatsuo Shimosawa, Miki Nagase, Toshiro Fujita

    Hypertension (Dallas, Tex. : 1979)   52 ( 2 )   287 - 94   2008.8

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    Metabolic syndrome is a highly predisposing condition for cardiovascular disease and could be a cause of excess salt-induced organ damage. Recently, several investigators have demonstrated that salt loading causes left ventricular diastolic dysfunction associated with increased oxidative stress and mineralocorticoid receptor activation. We, therefore, investigated whether excess salt induces cardiac diastolic dysfunction in metabolic syndrome via increased oxidative stress and upregulation of mineralocorticoid receptor signals. Thirteen-week-old spontaneously hypertensive rats and SHR/NDmcr-cps, the genetic model of metabolic syndrome, were fed a normal salt (0.5% NaCl) or high-salt (8% NaCl) diet for 4 weeks. In SHR/NDmcr-cps, salt loading induced severe hypertension, abnormal left ventricular relaxation, and perivascular fibrosis. Salt-loaded SHR/NDmcr-cps also exhibited overproduction of reactive oxygen species and upregulation of mineralocorticoid receptor-dependent gene expression, such as Na(+)/H(+) exchanger-1 and serum- and glucocorticoid-inducible kinase-1 in the cardiac tissue. However, in spontaneously hypertensive rats, salt loading did not cause these cardiac abnormalities despite a similar increase in blood pressure. An antioxidant, tempol, prevented salt-induced diastolic dysfunction, perivascular fibrosis, and upregulation of mineralocorticoid receptor signals in SHR/NDmcr-cps. Moreover, a selective mineralocorticoid receptor antagonist, eplerenone, prevented not only diastolic dysfunction but also overproduction of reactive oxygen species in salt-loaded SHR/NDmcr-cps. These results suggest that metabolic syndrome is a predisposed condition for salt-induced left ventricular diastolic dysfunction, possibly via increased oxidative stress and enhanced mineralocorticoid receptor signals.

    DOI: 10.1161/HYPERTENSIONAHA.108.111815

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  • Two cases of renovascular hypertension and ischemic renal dysfunction: reliable choice of examinations and treatments. International journal

    Katsuyuki Ando, Katsutoshi Takahashi, Shigeru Shibata, Hiromitsu Matsui, Megumi Fujita, Yugo Shibagaki, Tatsuo Shimosawa, Masashi Isshiki, Toshiro Fujita

    Hypertension research : official journal of the Japanese Society of Hypertension   27 ( 12 )   985 - 92   2004.12

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    We experienced two aged patients with atherosclerotic renovascular stenosis associated with hypertension and ischemic nephropathy. Both patients exhibited sudden rise in blood pressure (BP) and progressive aggravation of renal dysfunction. In these patients, the use of contrast medium to screen for renal artery stenosis (RAS) ran the risk of further deterioration of renal function. We therefore used magnetic resonance angiography (MRA), which is less conducive to renal damage, to screen for RAS. One-sided RAS was treated by percutaneous transluminal angioplasty of the renal artery (PTRA) and stenting. As a result, BP decreased in both patients. Serum creatinine (Cr) decreased slightly in one patient, whereas, in the other, serum Cr increased transiently and then decreased and stabilized to pre-treatment levels. Thus, although it is unclear whether the combination of PTRA and stenting is among the best treatments for patients with RAS and moderate-to-severe renal dysfunction, PTRA and stenting are clearly of benefit in selected patients. In addition, recent progress in characterizing the pathophysiology of ischemic nephropathy associated with renovascular hypertension has created interest in the therapeutic potential of angiotensin II receptor antagonists, sympatholytic agents, and antioxidants. Therefore, we discuss the therapeutic utility of PTRA and stenting and the above-mentioned medications in patients with RAS and renal dysfunction.

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