【摘要】 目的 :观察自发性高血压大鼠 (SHR)心肌间小血管平滑肌细胞 (SMCs)Bcl 2和Bax蛋白的表达及心肌细胞凋亡指数(APOI) ;同时观察血管紧张素Ⅱ 1型受体 (AT1R)拮抗剂 厄贝沙坦对SHR心肌间小血管SMCsBcl 2和Bax蛋白表达及心肌细胞凋亡的影响。方法 :2 4只 16周龄SHR等分为厄贝沙坦 (30mg/kg/d ,2 0w)组和非厄贝沙坦组 ,另选 16周龄Wistar大鼠 (12只 )作为正常对照组。分别采用SP免疫组化法和末端脱氧核苷酸转移酶介导dUTP缺口末端标记法 (TUNEL)及病理检查方法检测Bcl 2和Bax蛋白水平的表达和APOI。结果 :非厄贝沙坦组与正常对照组比较 :收缩压明显增高 (P <0 0 1) ,左室重量指数 (LVW/BW)明显增加 (P <0 0 5 ) ;心肌间小血管SMCsBcl 2蛋白的表达明显增强 (P <0 0 5 ) ,心肌细胞APOI明显增加 (P<0 0 5 ) ,而Bax蛋白的表达两组无显著差别。厄贝沙坦组与非厄贝沙坦组比较 :收缩压明显降低 (P <0 0 1) ,LVW /BW明显下降 (P <0 0 5 ) ;SMCsBcl 2蛋白的表达及心肌细胞APOI明显减少 (P <0 .0 5 ) ,Bax蛋白的表达明显增强 (P <0 0 5 )。厄贝沙坦组与正常对照组比较 :Bax蛋白表达明显增强 (P <0 0 5 ) ,Bcl 2蛋白表达和APOI无明显差别。结论 :①SHR的小血管SMCs的凋亡受到抑制可能与Bcl 2蛋白的过度表达有关更多还原

【Abstract】 Objective: To investigate the expression of the proteins Bcl-2 and Bax in intramycardial arteries of SHR and Wistar rats,and the effects of angiotensinⅡ Type-1 receptor(AT 1R) antagonist-Irbesartan on the expression of proteins Bcl-2 and Bax and cardiomyocyte apoptosis in rats.Methods: Twenty-four rats were divided into Irbesartan group( n =12) and the group without Irbesartan( n =12) 12 rats as normal control group were chosen.The expression of the proteins Bcl-2 and Bax was determined by Immunhistochemia,cardiomyocyte apoptosis was identified by in situ TDT-mediated dUTP nick end labeling(TUNEL).Results:Compared with the normal control group,untreated SHR exhibited increased systolic blood pressure,left ventricular mass index,Bcl-2 expression,cardiomyocyte apoptosis inde (APOI) and similar Bax expression.Compared with the group without Irbesartan,systolic blood pressure was decreased,left ventricular mass index and Bcl-2 expression were significantly lower,APOI was reduced significantly in the Irbesartan group.Irbesartan group showed higher Bax expression than the group without Irbesartan and normal control group. Conclusion: The findings suggest that smooth muscle cell apoptosis may be inhibited in small arteries of adult SHR as a consequence of an excess of the protein Bcl-2.In addition,The results suggest that chronic AT 1R antagonist--Irbesartan restore the susceptibility to apoptosis in these cells through stimulation of the protein Bax.These results indicate that Irbesartan effectively inhibits cardiomyocyte apoptosis and reverses left ventricular hypertrophy.更多还原