Effects of estrogen on SOD and MDA and apoptosis in hepatic ischemia-reperfusion injury of rats

Objective: To investigate the effects of estrogen on supemxide disnlutase(SOD),malondialdehyde(MDA) and apoptosis in hepatic ischemia reperfusion injury of rats.Methods: Models of rats with hepatic ischemia-reperfusion were established.Male S-D rats were randomly divided into three group: sham group,I/R group and I/R+E2 group.After 1,3 and 6 h of reperfusion,alanine aminotransferase in the serum were observed;the superoxide dismutase(SOD) activity and levels of malondialdehyde(MDA) in the hepatic tissue were detected;histologic changes of liver were compared;cell apoptosis were measured by flow cytometry.Results: The levels of ALT,MDA and cell apoptosis index in I/R+E2 group were lower than that in I/R group,but the activity of SOD increased.The obvious ischemia-reperfusion injury was observed under light microscope in I/R group,including congestion in liver sinusoids,hepatocyte swelling,inflammatory cell infiltration and necrosis of hepatocytes in some areas of the livers.In Sham group and I/R+E2 group,hepatic tissue injury was significantly improved.Conclusions: Estrogen significantly protects liver from hepatic ischemia-reperfusion injury.The mechanism of protection may be associated with its scavenging of radical,inhibition of lipid peroxidation and decrease of the hepatocellular apoptosis.