| OBJECTIVEThe aim of this study was to investigate the effects of diazoxide in myocardium ischemia/reperfusion injury and the role of autophagy.METHODSA rat model of Langendorff perfusion system was used.Thirty-second male Sprague-Dawley rats were randomly assigned to ischemia reperfusion controlled(group C),diazoxide treatment(100umol/L,group D),received the special autophagical inhibitor wortmannin(WT 15ug/kg ip.30 min before heart isolated) with(group DW) or without diazoxide(group W).All hearts intervention for 10 min agents after stabilization subjected 20 min of global ischemia followed by 30 min of reperfusion. HR,Left ventricular developed pressure(LVDP) and left ventricular end-diastolic pressure(LVEDP),maximum left ventricular pressure increase and decrease rate (±dp/dt)were recorded Autophagy was evaluated transmission electron microscopy (TEM) and the expression of autophagic marker protein Beclin-1 with immunochemistry staining,MDA and SOD were measured with commercial kits. RESULTSThere were no different in baseline and the time before ischemia(P>0.05).At the end of reperfusion,+dp/dt,LVDP and expression of autophagic related protein beclin-1 in group D were significant elevated compared with the other groups,and LVDEP, SOD,MDA value were decreased significant.CONCLUSIONDiazoxide exerts cardioprotective effects administered before ischemia.This effect is mediated by autophagy and blocked by autophagic inhibitor WT. |
