The Effects Of Propofol Or Midazolam On Cell Apoptosis Induced By Hepatic Ischemia-reperfusion In Rats

Objective To observe the effects of propofol or midazolam on cell apoptosis and apoptosis-regulating genes Bcl-2,Bax expression induced by hepatic ischemia-reperfusion in rats.To investigate they possible mechanisms against ischemia-reperfusion injury.Methods Seventy-two healthy SD rats weighing 250-300g were randomly divided into 4 groups as follows(n=18):sham-operated control group(Sham group),ischemia-reperfusion group(IR group),propofol group(P group) and midazolam group(M group).Each group divided 3 time phases at 1h,3h,6h after reperfusion.A rat model of hepatic ischemia-reperfusion was established.All rats were killed and the left hepatic lobes were sampled at the end of reperfusion.Light microscopy and electron microscopy were performed to verify the morphologic and ultrastructural changes of hepatic cell apoptosis.The apoptosis index(AI) of hepatic cell was measured by TUNEL method.Bcl-2 and Bax protein expression in liver tissue were assessed by immuno-histochemical method.Results①The result of light microscopy and electron microscopy:Compared with Sham group,IR group showed great changes.The pathological lesions were lighter in P,M group than in IR group.②The result of AI:Apoptosis index of hepatic cell were significantly higher between Sham group and IR,P,M groups(P＜0.05).AI was significantly lower in P,M groups than in IR group(P＜0.05).AI was higher in M group than in P group(P＜0.05).The result in three time phases of group IR,P,M reached the peak at 6h after reperfusion(P＜0.05).③The expression of Bcl-2,Bax:Bcl-2,Bax protein expression were significantly higher between Sham group and IR,P,M groups(P＜0.05).Bcl-2 protein expression was significantly higher,while Bax protein expression was significantly lower in P,M groups than in IR group(P＜0.05).Bcl-2 protein expression was lower,while Bax protein expression was higher in M group than in P group(P＜0.05).Conclusions Propofol and midazolam can relieve the liver cellular apoptosis by regulating Bcl-2 and Bax protein expression.They may protect liver from ischemia-reperfusion injury.And the protective effect of propofol is better than midazolam.