Significance of hepatocytes apoptosis in liver ischemia-reperfusion injury in cirrhotic rats

ObjectiveTo investigate whether hepatic ischemia-reperfusion (I/R) injury in cirrhotic rats is related to hepatocytes apoptosis and the high sensitivity to ischemia injury of cirrhotic liver is contributed to hepatocytes apoptosis. MethodsThe model of liver I/R injury was induced by Pringle maneuver. The cirrhotic rats were randomized into 2 groups: group A: ischemia time = 20 min; group B: ischemia time = 30 min; group C: normal controls, ischemia time = 30 min. The serum levels of AST and ALT and the percentage of apoptotic hepatocytes were compared among 3 groups and between pre-reperfusion and post-reperfusion. ResultsThe serum levels of AST and ALT were markedly elevated after I/R injury, reached its peak in 6 h after reperfusion and then gradually decreased. Six hours after the reperfusion, the serum levels of AST and ALT were significantly higher in group B than in other 2 groups (P0.05). The number of apoptotic hepatocytes was dramatically increased after I/R injury, reached its peak at the 6th h after reperfusion and then gradually decreased. Six hours after the reperfusion, 20.9% of apoptotic hepatocytes were seen in group B, which was significantly increased as compared with the other 2 groups (P0.01). There was no evidence of necrosis of hepatocytes during the period of reperfusion. ConclusionsLiver cell apoptosis is the major cell death in liver I/R injury in cirrhotic rat model. The severity of hepatocyte apoptosis is highly related to the time of ischemia. The high sensitivity of cirrhotic liver to ischemia injury is also related to hepatocytes apoptosis.