Relevance of hepatocellular apoptosis and expression of Bcl-2 protein in rats during hepatic ischemia-reperfusion.

Objective To investigate the relcvance of hepatocellular apoptosis and the expression of Bcl-2 protein in rats during hepatic ischemia-reperfusion.Methods With a rat model of hepatic ischemia-reperfusion, 72 healthy male Wistar rats were randomly divided into 3 groups: normal group、sham-operation group and ischemia-reperfusion group. The Bcl-2 protein content in heaptic tissue was measured by immunohistochemical analysis. Moreover, the hepatocellular apoptosis was detected by TdT-mediated dUTP-biotin nick end labeling (TUNEL) and electronmicroscropy.Results The content of Bcl-2 protein in ischemia-reperfusion group were markedly lower than that in the normal and sham-operation groups, Where as the hepatocellular apoptotic index (HAI) in ischemia-reperfusion group was markedly higher than that in the normal and sham-operation groups. The Bcl-2 protein reached its lowest and HAI value approached its peak level 3 to 6 hours after reperfusion. Moreover, In each phase of reperfusion, Bcl-2 protein level and HAI showed negative correlation significantly.Conclusion The down-regulation of the expression of Bcl-2 protein induces hepatocellular apoptosis during hepatic ischemia-reperfusion injury.