雷米普利对糖尿病大鼠心肌缺血/再灌注损伤的保护作用

目的研究雷米普利(RAM)对糖尿病大鼠心肌缺血/再灌注损伤的保护作用。方法链脲佐菌素致糖尿病大鼠被随机分为缺血/再灌注(I/R)、缺血预适应(IPC)和RAM3组。RAM组每天用RAM(1mg·kg-1)灌胃,IPC和I/R组用等体积生理盐水灌胃。4wk后各组动物均经历心肌缺血/再灌注损伤,IPC组于缺血前行心肌缺血预适应。连续监测心电图,检测心肌梗死范围、心肌细胞凋亡、凋亡蛋白Bcl-2与Bax表达,光镜下观察心肌形态学改变。结果与I/R组比较,RAM及IPC组ST-段抬高幅度降低,室早出现时间推迟,持续时间缩短,室速、室颤发生率降低,心肌梗死范围缩小,心肌细胞凋亡减轻,Bcl-2/Bax比值升高。结论连续4wk应用RAM可减轻糖尿病大鼠心肌缺血/再灌注损伤。

Study on cardioprotection of ramipril against ischemia/reperfusion injury in diabetic rats

Aim To investigate the effect of ramipril on myocardial ischemia-reperfusion injury in diabetic rats.Methods Streptozotocin induced diabetic rats were divided randomly into ischemia/reperfusion(I/R),ischemic preconditioning(IPC) and ramipril(RAM) groups.Rats in RAM group were administered RAM(1 mg·kg-1) orally for 4 weeks,the others were administered normal saline.Then all rats were subjected to myocardial ischemia/reperfusion injury.Rats in IPC group were preconditioned before ischemia.ECG,myocardial infarct size,apoptosis and expressions of Bcl-2 and Bax,changes of myocardial morphology were examined.Results Compared with those of I/R group,the elevation of ST segment and the incidence of ventricular tachycardia and ventricular fibrillation during ischemia were significantly decreased,myocardial infarct size and cardiomyocyte apoptosis index were remarkably reduced,ratio of Bcl-2/Bax was increased in both IPC and RAM groups.Conclusion Myocardial ischemia/reperfusion injury was decreased in diabetic rats after ramipril orally administered for 4 weeks.