[The role of nitric oxide in the angiotensin II-induced hypertrophy of cardiac myocytes].
The purpose of this study was to determine the role of nitric oxide (NO) in the angiotensin II-induced hypertrophic response in cultured neonatal rat cardiac myocytes. Angiotensin II induced significant increase of protein content, decrease of NOS activity in cultured neonatal rat cardiomyocytes and decrease of NO concentration in the culture medium. Angiotensin II decreased significantly the eNOS mRNA level of cardiomyocytes. Saralasin and PTX inhibited significantly the increased protein content, the decreased NOS activity and the decreaseed NO production of cardiomyocytes induced by angiotensin II. Sodium nitroprusside increased significantly NO concentration in the culture medium and inhibited significantly the increased protein content of cardiomyocytes induced by angiotensin II. The results suggest that angiotensin II may induce hypertrophy of cultured neonatal rat cardiomyocytes. The effect of angiotensin II is mediated by receptors which are coupled with PTX-sensitive G protein and may be related to the decreased eNOS gene expression, NOS activity and NO production. Exogenous NO can prevent the hypertrophy of cardiomyocytes induced by angiotensin II.
Zhan
C D
CD
Department of Physiology, Sun Yat-sen University of Medical Sciences, Guangzhou 510089.
Wang
T H
TH
Pan
J Y
JY
D000804:Angiotensin II; D000818:Animals; D000831:Animals, Newborn; D006332:Cardiomegaly / Q000473:pathology* / Q000517:prevention & control; D002478:Cells, Cultured; D009206:Myocardium / Q000166:cytology* / Q000473:pathology; D009569:Nitric Oxide / Q000502:physiology*; D019001:Nitric Oxide Synthase / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III; D051381:Rats; D017207:Rats, Sprague-Dawley
D000804:Angiotensin II; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D052250:Nitric Oxide Synthase Type III; C496316:Nos3 protein, rat