氯沙坦对心力衰竭大鼠心肌细胞Bax、Bcl-2蛋白表达的影响

目的:探讨氯沙坦对心力衰竭大鼠心肌细胞促凋亡蛋白Bax和抗凋亡蛋白Bcl-2的影响。方法:选24只雄性8周龄SD大鼠,分为对照组、心衰组和氯沙坦干预组各8只。采用阿霉素腹腔注射造模,氯沙坦干预组同时灌胃给氯沙坦连续给药6周。用原位脱氧核糖核酸酶未端标记法(TUNEL法)检测大鼠心肌细胞凋亡,用免疫组化法检测大鼠心肌Bax、Bcl-2蛋白的表达。结果:与对照组比较,心衰组心肌细胞凋亡指数升高,提示心衰组存在明显心肌细胞膜损伤。与心衰组比较,氯沙坦干预组心肌细胞凋亡指数降低。心衰组和氯沙坦干预组心肌细胞Bax和Bc1-2基因蛋白表达显著高于对照组,与心衰组相比,氯沙坦干预组明显下调Bax基因表达,上调Bc1-2基因表达。结论:氯沙坦可明显提高抗凋亡蛋白Bcl-2蛋白表达,降低促凋亡蛋白Bax蛋白表达,提示氯沙坦具有有效抑制心肌细胞凋亡,改善心衰作用。

Effects of Iosartan on the myocardial cells Bax,Bcl-2 protein expression of heart-failure rats

Objective：To observe the influence of Iosartan on myocardial cells pro-apoptotic protein Bax and anti-apoptosis protein Bcl-2 in heart-failure rats.Methods：24 SD male rats（8 weeks） were divided into three groups：the control group,heart-failure group,and treatment group.Each group would have eight rats.We used ADM intraperitoneal injection model,and at the same time the treatment group gavaged to Iosartan for six weeks.DNA-situ terminal labeling（TUNEL method） was used to detect myocardial apoptosis,while myocardial Bax,Bcl-2 protein expression was detected by immunohistochemistry.Results：Compared to the control group,myocardial apoptosis index of heart-failure group increased significantly,which showed that there existed evident damage in the myocardial cells of heart-failure group.Compared to heart-failure group,myocardial apoptosis index of treatment group decreased.Myocardial cells Bc1-2 and Bax protein expression in heart-failure group and treatment group was obviously higher than that in the control group.Bax gene expression decreased and bal-2 gene expression increased in treatment group,when compared to control group.Conclusion：Losartan can significantly increase the Bcl-2 protein expression while decrease Bax protein expression,so as to efficiently suppress myocardial apoptosis and improve heart failure.