| Background: Acute myocardial infarction most effective treatment measures are ischemic myocardial reperfusion,it can reduce the infarct size,improve the prognosis.However,in recent years more and more evidence show that:after reperfusion over a period of time increase myocardial injury ,may appear reperfusion arrhythmias,myocardial stunning and cell necrosis,etc,it is myocardial ischemia-reperfusion injury.This is a complex pathophysiological process, apoptosis in myocardial ischemia-reperfusion is the death of an important mechanism of myocardial.The study shows that :apoptotic factor Bcl-2 and Bax interaction are the regulation of apoptosis center,the study of apoptosis factor Bcl-2/Bax in myocardial ischemia-reperfusion injury and its mechanism,from gene level to take corresponding measures to control regulation of myocardial cell ischemia-reperfusion injury,will have far-reaching theoretical and clinical application.Objective: Recently,numerous studies have shown that the renin-angiotensin system with myocardial ischemia-reperfusion injury occurring in cardiomyocyte apoptosis are closely linked, but the composition of RAS in myocardial ischemia-reperfusion injury in the mechanism is still far from clear.The I-R heart model was established by ligating the left anterior descending branch of coronary artery in Wistar rats.The present study was undertaken to test the effect of angiotensin converting-enzyme inhibitor,Perindopril on ischemia-reperfusion model of rat cardiomyocyte apoptosis and apoptosis-related proteins Bax, Bcl-2 expression.Methods:I-R model in rats was established by the ligation of left anterior descending coronary.Wistar rats were randomized to I-R control group(n=12), Perindopril group(2mg/kg,n=12),the rats without operation were put into the sham-operated group(n=12) . The rats were infused with 4mg/kg of perindopril into vein in perindopril group and equal quantity of normal saline in IR group and sham-operated group before ligating the LADs 45 minutes.haemodynamics parameters which included left ventricular systolic pressure(LVSP),left ventricular end-diastolic pressure (LVEDP),left ventricular pressure maximal rate of rise and fall(dP/dTmax and dP/dTmin) were measured. The biopsy heart tissue with 4% formalin fixation and their chips with paraffin imbedding were made after experiment, and their apoptosis and Bcl-2 and Bax protein were detected by TUNEL and S-P immunohistochemical method, respectively.Result: Compared with sham-operated group rats,LVSP,dP/dTmax and dP/dTmin of all operated groups were significantly reduced (P<0.01), LVEDP were significantly increased(P<0.01). Compared with I-R control group,LVSP,dP/dTmax and dP/dTmin of perindopril group were significantly increased (P<0.01), LVEDP were significantly reduced (P<0.01). Myocardium of sham-operated group had no obvious cardiac myocyte apoptosis and 45min ischemia reperfusion after 4h the occurrence of cardiomyocyte apoptosis,Bcl-2 protein-positive staining cells increased, Bax-positive cells also increased significantly in order to increase Bax protein expression mainly.Perindopril group of cardiac myocyte apoptosis index, myocardial protein expression of Bax was significantly lower than ischemia-reperfusion group(P<0.01),Bcl-2 protein expression had no obvious change.Conclusion:Apoptosis can be expressed in cadiocytes with ischemia- reperfusion,the process of myocardial ischemia-reperfusion myocardial apoptosis,myocardial cells in Bax,Bcl-2 protein expression is a dynamic change,Bax protein and Bcl-2 protein co-regulation of cardiomyocyte apoptosis.Perindopril can reduce the number of cardiomyocyte apoptosis, inhibition may be associated with reduced expression of Bax protein. |
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