Effects Of Exendin-4 On Myocardial Apoptosis And Expression Of Bcl-2 And Bax Protein In Ischemia-reperfusion Rats

Objective:To study the effects of Exendin-4 on cardiomyocyte apoptosis following ischemia-reperfusion in vitro and the expression of Bcl-2 and Bax proteins.Methods:The myocardial ischemica-reperfusion injury model in rats were established by ligating left anterior descending(LAD) coronary artery(ischemia 30 min,reperfusion 120min),then the hearts were took out.Healthy Sprague-Dawley rats were randomly divided into 3 groups(n=8 each): sham-poeration group, ischemica-reperfusion group and Exendin-4 group.Apoptosis was identified by TUNEL and apoptosis index(AI) was obtained.The protein expression of Bax and Bcl-2 genes was detected by using immunohistochemical technique, and the mean optical dennsity(OD) values of the positive fields of protein expression were quantitatively examined by usig image analysis system.Results:(1) Compared with sham-operation group, I/R group and Exendin-4 group Bcl-2 and Bax expression levels were increased(P<0.05),difference were significant.myocardial apoptosis index were increased(P<0.05),difference were significant;(2) Compared with I/R group,Exendin-4 group Bcl-2 expression levels were increased(P<0.05),difference were significant.Bax expression levels were decreased(P<0.05),difference were significant;(3) myocardial apoptosis index were decreased(P<0.05), difference were significant.Conclusions:Exendin-4 maybe inhibit effectively the apoptosis of cardiac myocytes in rats with myocardial ischemica-reperfusion injury with the regulation of Bcl-2 and Bax protein expression levels.