The anti-apoptosis effect on myocardium of HSP70 in non-invasive limb ischemia preconditoning

Objective To investigate the effect of non-invasive limb ischemic preconditioning on myocardium apoptosis and HSP70 expression.Methods Male healthy adult Wistar rats weighing 200-300 g were used for this study.The rats were randomly assigned to four groups:control(A),ischemia/reperfusion(B),classic ischemic preconditioning(C),and remote ischemic preconditioning(D).Electrocardiogram were recorded during myocardial infarction and reperfusion.At the end of reperfusion,serum creatine kinase(CK),CK-MB,apoptosis index of myocardial cells with the methods of TUNEL,the expression of HSP70 using immunohistochemistry,area of the heart ischemia(area at risk AAR),the scope of infarction(infracted area,IA)and IA/AAR ratio were determined.Results (1)CK and CK-MB:The level of CK and CK-MB of C,D group were lower than B group(P0.05).(2)Myocardial infarction area(IA/AAR):Myocardial infarction area(IA/AAR)of C,D group were lower than B group(P0.05).(3)Apoptosis index:the apoptosis index of C,D group were lower than B group(P0.05).(4)HSP70:The expression of HSP70 of C,D group were higher than B group(P0.05).Conclusions We conclude that non-invasive limb ischemic preconditioning,as well as classic ischemic preconditioning,have cardioprotective effect which may be partly induced by increasing the level of HSP70 to inhibit apoptosis of myocardium.