Effects of preconditioning on myocardial ischemic reperfusion injury of rats

Objective To study the effect of ischemic preconditioning and sufentanil precondition on myocardium against ischemia/reperfusion(I/R) injury.Methods The myocardial ischemia and reperfusion injury model was built.The animals were randomly divided into 4 groups: sham group(n=12);control group(CON,n=12);ischemic preconditioning group(IPC,n=12) and sufentanil preconditioning group(SPC,n=12).In control group the hearts were subjected to 30 min ischemia followed by 90 min reperfusion(I/R).In IPC group the hearts were subjected to 3 episodes of 5 min ischemia in succession at 5 min interval for reperfusion before I/R.In SPC group the animals received 3 periods of 5 min remifentanil infusion at 1ug/kg at 5min interval before I/R.HR,MAP and RPP were recorded before and after I/R.At the end of 90 min reperfusion,arterial blood was obtained,and then MB isoenzyme of creatine kinase(CKMB) and lactic dehydrogenase(LDH) were measured.Infarct size(IS) and the area at risk(AAR) were determined by triphenyltetrazolium staining.Results In the ischemia and reperfused period,MAP and RPP were significantly lower in the control group compared with that of sham group(P0.01),which were higher in the IPC and SPC groups than those of control group(P0.05,P0.01).In the ischemia and reperfused period,CK-MB and LDH was obviously lower in the IPC and SPC groups than that of control group(P0.05).Conclusion Sufentanil and IPC has similar protective effect on the heart against I/R injury