ABSTRACT
Objective To investigate the protective effects of propofol preconditioning on myocardium against hypothermia ischemia normothermia reperfusion injury on isolated rat hearts. Methods The Langendorff apparatus was used.Sixty SD rat hearts were divided randomly into 5 groups after 20-minute equilibrium(n=12): control(Con) group,hearts were continually perfused with K-H buffer for 175 min;ischemia/reperfusion(I/R) group,hearts were perfused with K-H buffer for 40 min,then subjected to global ischemia at 27 ℃ for 75 min,and followed reperfusion at 37 ℃ for 60 min;propofol preconditioning group 1(P1),group 2(P2),and group 3(P3),hearts were perfused with K-H buffer including 50,100,and 150 ?mol/L propofol for 10 min and followed reperfusion like I/R group,respectively.Heart rate(HR),left ventricular end-diastolic pressure(LVEDP), left ventricular developed pressure(LVDP) and ?dp/dtmax at the end of equilibration,pre-ischemia and at the end of reperfusion were recorded.The contents of creatine kinase(CK) and lactate dehydrogenase(LDH) in coronary effluent were measured at the end of equilibration and 1,10,20,30,and 60 min during reperfusion.The activity of superoxide dismutase(SOD) and the contents of maleic dialdehyde(MDA) were measured at the end of reperfusion.The area of infarct region was determined at the end of reperfusion. Results HR,LVDP,?dp/dtmax and SOD activity in P2 and P3 group were higher than those in I/R group(P