急性缺血再灌注家兔心肌组织中半胱氨酸蛋白酶-3的表达和细胞凋亡及对心室功能的影响

目的观察家兔急性缺血再灌注后心肌组织中半胱氨酸蛋白酶-3(Caspase-3)表达和细胞凋亡的变化及对心室功能的影响。方法30只家兔随机分为对照组、缺血组和再灌注组,每组10只。缺血组套扎左冠状动脉前降支30min,再灌注组套扎30min后再灌注120min,对照组游离左冠状动脉前降支不结扎。超声心动图测量左心室收缩功能,原位末端标记检测法(TUNEL)检测细胞凋亡数,反转录-聚合酶连反应(RT-PCR)检测Caspase-3 mRNA的表达,免疫组织化学法检测Caspase-3蛋白的表达。结果缺血组与对照组比较,Caspase-3蛋白表达增高(P<0.05),Caspase-3mRNA表达显著增强(P<0.01),心肌TUNEL阳性细胞数无明显升高(P>0.05),左心室应变率明显降低(P<0.01);再灌注组与缺血组比较,Caspase-3和Caspase-3 mRNA蛋白表达均有所增强(P<0.05),心肌TUNEL阳性数明显增加(P<0.01),左心室应变率有所恢复(P<0.01);再灌注组与对照组比较,各指标均有显著性差异(P<0.01)。结论缺血再灌注激活Caspase-3,导致心肌细胞的凋亡,二者与心室功能的改变存在一定内在联系。

Influence of the expression of Caspase-3 and apoptosis on left ventricular functions in rabbits with acute myocardial ischemia reperfusion

Objective To observe the influence of the expression of Caspase-3 and apoptosis on left ventricular function in rabbits with acute myocardial ischemia reperfusion.Methods Thirty rabbits were divided into control group,ischemia group and reperfusion group randomly,ten rabbits in every group.Left anterior descending coronary artery(LAD)were ligated 30 minutes in ischemia group,were reperfusion 120 min following ligated LAD 30 min in reperfusion group,without LAD ligation in control group.The left ventricular function were detected by Echocardiogram,the percentage of apoptosis was detected by terminal deoxy-nudeotidy transferease-mediated biotinylated deoxyuridine triphosphate nick end labeling(TUNEL).Caspase-3 mRNA and protein expression were analyzed by RT-PCR and by immunohistochemical method.Results Caspase-3 mRNA and protein expression increased more significantly in ischemia group than that in control group(P<0.05),and increased significantly in reperfusion group(P<0.01).The peak strain rate(SRpeak)in ischemia group decreased obviously(P<0.01),and increased slightly after reperfusion 120 min,but still decreased than control group(P<0.05).The positive cell of TUNEL had no significant difference between ischemia group and control groups(P>0.05),and increased in reperfusion group(P<0.01).Conclusion Myocardial Ischemia Reperfusioncan activate the Caspase-3,cause myocardial cells apoptosis,which are related to the left ventricular function.