Influence of glibenclamide on ATP-sensitive potassium channels in the cardiac ischemic preconditioning against myocardial ischemia-reperfusion injury

Objective:To study influence of glibenclamide on ATPsensitive potassium channels (K ATP ) in the effect on cardiac ischemic preconditioning (IP) against myocardial ischemiareperfusion injury. Methods: Fortyfour rats were divided into preconditioning group(IPC group),glibenclamide group(GLI group),glibenclamidepreconditioning group(GP group) and control group(C group). The preconditioning protocol consisted of 3 cycles of 10 minutes local ischemia and 3 cycles of 10 minutes reperfusion.The rats were subjected to 30 minutes of local ischemia followed by 60 minutes of reperfusion.The infarct size was measured by nitroblue tetrazolium and red tetrazolium staining.Results:IPC could result in marked reduction of infarct size,which was completely abolished by glibenclamide.IPC could also reduce the occurrence of ventricular arrhythmias induced by ischemiareperfusion,which failed to be blocked by glibenclamide.Conclusions:Glibenclamide can influence K ATP in cardiac protection of the intact rat IPC heart.