Effects and mechanisms of insulin postconditioning on myocardial protection in isolated rat hearts / 重庆医科大学学报

ABSTRACT

Objective:To explore the effects and mechanisms of insulin postconditioning on myocardial protection in isolated rat hearts.Methods:32 Wistar rats were randomly divided intocontrol group,ischemia/reperfusion group(I/R group),low dose insulin postconditioning group(L-POST group)and high dose insulin postconditioning group(H-POST group),with 8 rats in each group.Langendorff and neely perfusion models were steadily established,then the rat hearts were arrested by cardioplegia(St.Thomas No.2 solution,STH-2)after perfusion for 30 min.These arrested hearts were remained for 30 min at 4℃and then underwent reperfusion for 60 min.In L-POST group and H-POST group,the arrested hearts were reperfused by Krebs-Henseleit buffer solution(K-H)with insulin.The content changes of myocardial eNOS and PKC were detected by immunohistochemistry and Western blo(tWB),the AI(Apoptosis index,AI)of cardiomyocyte was detected by TUNEL.Results:Compared with control group,higher expression of eNOS and PKC and higher AI were detected in I/R group、L-POST group and H-POST group (P