Expression of caraiomyocyte angiotensin II receptors in rat with pressure over load-induced left ventricular hypertrophy

Objective:To investigate the role of AngⅡreceptors(AT1 and AT2) in the left ventricular hypertrophic process and its mechanisms through detecting the expression of AngⅡreceptors(AT1 and AT2) in hypertrophic cardiomyocyte induced by pressure overload in rats. Methods:Fourteen Male Sprague-Dawley rats were divided into two groups: sham group(n=7),and operation group(n=7). Left ventricular hypertrophy model was well established after abdominal aortic stenosis in each group.The expression of AT1 and AT2 was detected by immunohistochemistry(IHC) and RT-PCR,respectively. Indexes of left ventricular hypertrophy,including myocardial fibrosis,LVMI,cross-sectional area and apoptosis index(APOI),were also measured. Results: SBP,DBP,MBP,LVMI,and cardiomyocyte CSA,APOI,level of plasma AngⅡand expression of AT1 and AT2 in operation group were markedly increased as compared with sham group. Conclusion:Expression of cardiomyocyte AT1 and AT2 receptors were increased significantly in rat of left ventricular hypertrophy,which indicated that AT1 and AT2 receptors both participate in the process of left ventricular hypertrophy but they may play antagonism effects.