ANGIOTENSIN Ⅱ-INDUCED APOPTOSIS IN CULTURED ADULT RAT VENTRICULAR MYOCYTES

VernacularTitle:血管紧张素Ⅱ诱导培养的成年大鼠心肌细胞凋亡
Author: Xun GUO ¹ ; Zhao-Gui GUO
Author Information

1. 湖南医科大学
Keywords: angiotensin Ⅱ; apoptosis; losartan; cardiomyocyte; rat
From: Acta Physiologica Sinica 1998;50(4):416-422
CountryChina
Language:Chinese
Abstract: Angiotensin Ⅱ (Ang Ⅱ )-induced apoptosis was demonstrated for the first time in cultured adult rat ventricular myocytes (ARVMs) isolated by retrograde heart perfusion with Krebs-Henseleit bicarbonate (KHB) buffer containing collagenase and hyaluronidase. ARVMs incubated with 10 μmol/L Ang Ⅱ for 48 h showed morphological features of apoptosis (cellular shrinkage, condensation of cytoplasm) and a characteristic "ladder" of DNA bands representing integer multiples of the intemucleosomal DNA length about 180～ 200 bp, which became more evident with further incubation up to 72 h. With shorter incubation time ( ≤24 h) or at a lower AngⅡ concentration ( ＜ 10μmol/L), such changes failed to occur. This effect of Ang Ⅱ could be abolished by losartan (10 μmol/L), verapamil (1 μmol/L) or staurosporine (10 nnol/L). The above results indicate that Ang Ⅱ -induced apoptosis in ARVMs may be mainly mediated by Ang Ⅱ type Ⅰ(AT1) receptors with [Ca2+ ]i and protein kinase C (PKC) playing a critical role.