Search

Your search keyword '"Yasunari, Kenichi"' showing total 218 results
Start Over Author "Yasunari, Kenichi"
218 results on '"Yasunari, Kenichi"'

5. Phosphoinositide turnover signaling stimulated by ET-3 in endothelial cells from spontaneously hypertensive rats

Author

Yokokawa, Koji, Johnson, Joy, Kohno, Masakazu, Mandal, Anil K., Yanagisawa, Masashi, Horio, Takeshi, Yasunari, Kenichi, and Takeda, Tadanao

Subjects
Rats -- Physiological aspects, Endothelin -- Physiological aspects, Phosphoinositides -- Physiological aspects, Biological sciences
Abstract

Comparative studies of the role of endothelin (ET) B-type receptor in the phosphoinositide turnover signaling in cultured aortic endothelial cells of the Wistar-Kyoto (WKY) and spontaneously hypertensive (SHR) strains of hypertensive rat models reveal that ET receptor-mediated signal transduction is higher in the SHR strain than in the WKY strain. The mobilization of Ca(2+) from intracellular stores stimulation of protein kinase C is higher in SHR-based cells than in WKY-based cells after ET-3 addition.

Published
1994

6. Dopamine DA1 receptors on vascular smooth muscle cells are regulated by glucocorticoid and sodium chloride

Author

Yasunari, Kenichi, Kohno, Masakazu, Yokokawa, Koji, Horio, Takeshi, and Takeda, Tadanao

Subjects
Vascular smooth muscle -- Research, Dopamine receptors -- Physiological aspects, Corticosteroids -- Physiological aspects, Biological sciences
Abstract

Adenylate cyclase assays, tissue cultures and cAMP measurements in the vascular smooth muscle cells of rats show that sodium chloride and glucocorticoid regulate the dopamine DA1 receptors through different mechanisms and cause low adenylate cyclase function and low receptor affinity, and high cyclase activity and receptor activity. Glucocorticoid elevates cAMP response to dopamine to increase receptor activity and adenylate cyclase affinity. Glucocorticoid antagonist or cyloheximide inhibit the glucocorticoid's effect on the DA1 receptors.

Published
1994

7. Endothelin modulates the mitogenic effect of PDGF on glomerular mesangial cells

Author

Kohno, Masakazu, Horio, Takeshi, Yokokawa, Koji, Yasunari, Kenichi, Kurihara, Naotsugu, and Takeda, Tadanao

Subjects
Endothelin -- Physiological aspects, Platelet-derived growth factor -- Research, Biological sciences
Abstract

Endothelin regulates the mitogenic effect of platelet-derived growth factor (PDGF) on glomerular mesangial cells. The PDGF isoforms, AB and BB, activate endothelin-1 (ET-1) secretion in mesangial cells through PDGF beta-receptors. Endogenously-produced ET-1 regulates the mitogenic effect of PDGF AB and BB through A-type endothelin (ETa) receptors in cells. Treatment of rats with ETa receptors decreases renal mass limited glomerular damage and inhibits renal function impairment.

Published
1994

8. Cardiac hypertrophy and brain natriuretic peptide in experimental hypertension

Author

Kohno, Masakazu, Fukui, Toshiki, Horio, Takeshi, Yokokawa, Koji, Yasunari, Kenichi, Yoshiyama, Minoru, Kurihara, Naotsugu, and Takeda, Tadanao

Subjects
Natriuretic peptides -- Research, Malignant hypertension -- Analysis, Corticosterone -- Analysis, Hydralazine -- Analysis, Biological sciences
Abstract

Chronic treatment with enalapril and MK-954 decreases the ventricular weight and systolic blood pressure in deoxycorticosterone acetate salt-induced spontaneously hypertensive rats. The plasma concentrations of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) are reduced, but not to the levels seen in Wistar-Kyoto rats. Hydralazine causes enhanced ANP and BNP plasma concentrations when compared to enalapril and MK-954.

Published
1994

9. Natriuretic peptides inhibit mesangial cell production of endothelin induced by arginine vasopressin

Author

Kohno, Masakazu, Horio, Takeshi, Ikeda, Miwako, Yokokawa, Koji, Fukui, Toshiki, Yasunari, Kenichi, Murakawa, Koh-Ichi, Kurihara, Naotsugu, and Takeda, Tadanao

Subjects
Natriuretic peptides -- Physiological aspects, Cell proliferation -- Physiological aspects, Arginine -- Physiological aspects, Endothelin -- Physiological aspects, Peptides -- Physiological aspects, Biological sciences
Abstract

The effects of natriuretic peptides (NP) on the secretion of endothelin-1 (E-1) was studied in the mesangial cells of rat kidney glomerulus. Atrial NP and brain NP inhibits excessive excretion of E1 on contraction of mesangial cells and glomerular microcirculation by induction of ET-1 secretion by arginine vasopressin. C-type NP also inhibited EP-1 secretion to a lesser degree compared to ANP and BNP.

Published
1993

10. Interaction between a phorbol ester and dopamine DA(sub 1) receptors on vascular smooth muscle

Author

Yasunari, Kenichi, Kohno, Masakazu, Murakawa, Koh-Ichi, Yokokawa, Koji, Horio, Takeshi, and Takeda, Tadanao

Subjects
Blood pressure -- Regulation, Dopamine receptors -- Physiological aspects, Protein kinases -- Physiological aspects, Phorbol esters -- Physiological aspects, Vascular smooth muscle -- Physiological aspects, Vasoconstriction -- Research, Biological sciences
Abstract

The roles of protein kinase C, dopamine DA-1 receptors and cyclic adenylic acid (cAMP) in vasodilation and blood pressure regulation were investigated. The study protocol involved examination of the interaction between a phorbol ester and DA-1 receptors in rat vascular smooth muscle cells. The results indicate that protein kinase C induces an increase in the expression of DA-1 receptors, thus enhancing receptor-coupled generation of cAMP.

Published
1993

12. Brain natriuretic peptide as a marker for hypertensive left ventricular hypertrophy: changes during 1-year antihypertensive therapy with angiotensin-converting enzyme inhibitor

Author

Kohno, Masakazu, Horio, Takeshi, Yasunari, Kenichi, Ikeda, Miwako, Minami, Mieko, Kurihara, Naotsugu, and Takeda, Tadanao

Subjects
Neuropeptides -- Physiological aspects, Heart enlargement -- Diagnosis, ACE inhibitors -- Usage, Health, Health care industry
Abstract

Purpose: Secretion of brain natriuretic peptide (BNP), a cardiac hormone, is accelerated via hypertrophied ventricles in experimental hypertension. The present study examined whether regression of left ventricular (LV) hypertrophy by long-term treatment with an angiotensin-converting enzyme inhibitor (ACEI) affects plasma BNP concentration in patients with essential hypertension. Patients and Methods: Thirty-one hypertensive patients with LV hypertrophy were treated with ACEI (16 with enalapril; 15 with lisinopril) for 1 year. Serial changes were recorded in LV mass index, LV systolic function, and plasma concentrations of BNP and atrial natriuretic peptide (ANP). Results: ACEI therapy significantly reduced LV mass index at 6 months, and more so at 1 year. Septal and posterior wall thicknesses were also reduced. Plasma BNP and ANP were markedly elevated at study entry, but only BNP levels correlated with LV mass index. Both peptide levels declined after 6 months, and this decline was enhanced at 1 year. There was a close relation between BNP decline and LV mass index reduction overall and with enalapril and lisinopril separately. Changes in ANP and in LV mass index were not related. Conclusion: Long-term ACEI therapy can reduce elevated plasma BNP. in this study, changes in BNP reflected the magnitude of regression of LVH. Plasma BNP may be a useful marker for LVH during antihypertensive therapy in patients with essential hypertension and LVH.

Published
1995

14. Brain natriuretic peptide as a cardiac hormone in essential hypertension

Author

Kohno, Masakazu, Horio, Takeshi, Yokokawa, Koji, Murakawa, Koh-Ichi, Yasunari, Kenichi, Akioka, Kaname, Tahara, Akira, Toda, Iku, Takeuchi, Kazuhide, Kurihara, Naotsugu, and Takeda, Tadanao

Subjects
Cardiomyopathy, Hypertrophic -- Complications, Hypertension -- Diagnosis, Neuropeptides, Health, Health care industry
Abstract

PURPOSE: A natriuretic peptide, brain natriuretic peptide (BNP), has been isolated from porcine hearts. We performed this study to determine if BNP is secreted from the heart and to identify changes, if any, in the plasma BNP concentration in essential hypertension. PATIENTS AND METHODS: We measured the immunoreactive (ir) BNP concentration at intracardiac sites including the coronary sinus of five patients with heart disease during cardiac catheterization. We examined plasma ir-BNP in 48 hypertensive patients, 15 borderline hypertensive patients, and 25 normotensive subjects. RESULTS: Plasma ir-BNP in the coronary sinus was greater than at other cardiac sites. The concentration was significantly higher in hypertensive subjects than in borderline hypertensive or normotensive subjects. Hypertensive patients with left ventricular hypertrophy (LVH) established by echocardiography had higher plasma ir-BNP levels than those without LVH. In the hypertensive group, plasma ir-BNP was closely correlated with the LV mass index. In these patients, BNP levels were correlated with mean arterial pressure and inversely correlated with the LV ejection fraction, although these correlations were weak. Reverse-phase high-pressure liquid chromatography showed that the major component of circulating ir-BNP in the hypertensive and normotensive subjects corresponded to authentic human BNP-32. CONCLUSIONS: Human BNP-32 was secreted through the coronary sinus from the heart and may act as a cardiac hormone. Plasma BNP was increased in many of the hypertensive subjects with LVH. The increase in BNP seemed to be related to LVH or the cardiac overload associated with LVH.

Published
1992

18. Role of Angiotensin (1-7) in therapeutic application of inhibition of rennin-angiotensin system in man

Author

Ueda, Shinichiro, Yasunari, Kenichi, Shimabukuro, Michio, and Takishita, Shuichi

Subjects
アンジオテンシンII, 心不全, 酸化ストレス, Angiotensin II, NOクランプ法, 抗酸化作用, 降圧利尿薬臨床試験, アンジオテンシン(1-7), ACE阻害薬, Nitric Oxide, アンジオテンシン変換酵素, RCT of diuretics, 前腕血流量, oxidative stress, AGE inhibitor, ブラジキニン, プレシスモグラフ, bradykinin, angiotensin(1-7)
Abstract

平成13年度～平成15年度科学研究費補助金(基盤研究(C)(2))研究成果報告書, 研究概要:1.アンジオテンシン(1-7)の血管作用アンジオテンシン(1-7)をbrachial arteryより注入し、ヒト前腕抵抗血管におけるブラジキンンなどとの相互作用を検討した。アンジオテンシン(1-7)はそれ自体では血管拡張作用を有しないが、ブラジキニンの血管拡張作用を有意に増強した。この作用はACE阻害薬の投与下およびL-NMMAを用いてNOの産生抑制を行った場合も消失した。 2.ヒト血管NO研究におけるNOクランプ法のvalidation study ヒト抵抗血管においてLNMMAを動注してNOに関する実験を行う時、NOクランプ法を用いる妥当性を証明した。 3.アンジオテンシンIIの酸化ストレス増強作用と、アンジオテンシン(1-7)の抗酸化作用:in vivoおよびin vitroの検討ヒトマクロファージのモデルを作り、アンジオテンシンIIによる酸化ストレスをフローサイトメトリーで測定し、アンジオテンシン(1-7)の作用を検討した。アンジオテンシン(1-7)は、アンジオテンシンIIによる酸化ストレスの増加を用量依存性に抑制した。我々はまたアンジオテンシンIIは前腕抵抗血管においておそらく活性酸素産生増大によりNOドナーによる血管拡張作用を減弱させることを示したが、この実験系においてアンジオテンシン(1-7)はこのアンジオテンシンIIによる酸化ストレス増大を用量依存性に抑制した。 4.ACE阻害薬投与中の高血圧患者および心不全患者における血中アンジオテンシン(1-7)濃度 ACE阻害薬投与中の高血圧患者では非投与患者に比べ血中アンジオテンシンII濃度は差がないが、アンジオテンシン(1-7)濃度は有意に高値であった。またカプトプリル急性投与後の血圧の低下はアンジオテンシン(1-7)濃度上昇と相関した。心不全患者においてアンジオテンシン(1-7)は正常の 20-40倍と高値を示した。 5.降圧利尿薬臨床試験におけるレニンアンジオテンシン系マーカーの測定昨年開始された降圧利尿薬臨床試験のサブ研究としてアンジオテンシン(1-7)測定を予定している。, 要約(欧文):1.Interaction of Angiotensin(1-7) with bradykin and other vasoactive peptides in human resistant vessels in vivo Angiotensin(1-7) significantly potentiated vasodilating effect of bradykinin in dose-dependent manner possibly through NO system. This result is completely consistent with previous results from studies in isolated vessels. 2.Validation of NO clamp technique in human NO research in vivo We evaluated validity and feasibility of NO damp technique for NO research using L-NMMA for NOS inhibition. 3.Anticoxidant effect of Angiotensin(1-7) in vitro and in vivo We showed Angiotensin II attenuated vasodilating effect of a NO donor possibly through increased production of superoxide in human resisitant vessels. This effect was antagonized by co-infusion of Angiotensin(1-7) in dose dedpendent manner. Angiotensin(1-7) was also found to inhibit increased oxidative stress by Angiotensin II in cultured human THP-1 cells. 4.Increased Angiotensin(1-7) levels in patients with hypertension receiving ACE inhibitors. The single dose of captopril significantly elevated plasma levels of angiotensin-(1-7) in hypertensives and normal volunteers. There was highly significant correlation between changes in plasma levels of angiotensin-(1-7) and blood pressure. Plasma angiotensin-(1-7) levels in hypertensive patients chronically receiving ACE inhibitors were significantly higher than those without AGE inhibitors while there was no significant difference in plasma Angiotensin II levels. Either acute or chronic treatment with ACE inhibitors was associated with increased plasma levels of angiotennsin-(1-7), which may contribute to effects of ACF inhibitions., 未公開：P.4以降(別刷論文のため)

Published
2004

39. A Dopamine-Secreting Pheochromocytoma

Author

Yasunari, Kenichi, primary, Kohno, Masakazu, additional, Minami, Mieko, additional, Kano, Hiroaki, additional, Ohhira, Masakazu, additional, Nakamura, Kenji, additional, and Yoshikawa, Junichi, additional

Published
2000
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results