Experimental Studies On The Protective Effects Of Melatonin Against Hepatic Warm Ischemia-reperfusion Injury

Objective: To study the apoptosis and mitochondrial injury of hepatocyte induced by ischemia and reperfusion injury ,and study whether melatonin can attenuate the apoptosis and mitochondrial injury.Methods: Sprague-Dawley rats (350 ± 20g body weight) were randomly divided into sham operation group(sham group),hepatic ischemia-reperfusion injury model group(HIRI group)and melatonin treated groups(MT group).The MT groups was divided into treated before ischemia group and treated before reperfusion group.The apoptosis of hepatocyte was detected by terminal deoxynucleotidyl transferase mediated dUDP-biotin nick end labeling(TUNEL).The change of mitochandrial potential was analyzed by flow cytometry assay with DiOC6(3) staining.Hepatic mitochondria were isolated and the content of MDA, GSH were decteted.The serous ALT and AST were also detected.Result: Apoptosis of hepatocytes of HIRI groups is obviously severer than sham group,together with the raise of mitochondrial MDA ,the decrease of GSH and potential(P<0.05).The serous ALT and AST of HIRI group is obviously higher than that of sham group(P<0.05). While the apoptosis of MT treated group is lower than that of HIRI group,together with the raise ofmitochondrial potential and GSH, with the decrease of mitochondrial MDA.The serous ALT and AST of MT group were obviously lower than that of fflRI group(P<0.05).Conclusions: Apoptosis of hepatocyte exist in the rat liver during ischemia-reperfusion injury.Apoptosi is perhaps the result or form of ischemia-reperfusion injury,together with the mitochondrial oxidative stress.The melatonin can attenuate the apoptosis and mitochondrial injury through reducing oxidative stress.