Apoptosis and proliferation of intrahepatic bil educt after ischemia-reperfusion injury

BACKGROUND: In orthotopic liver transplantation, ische-mic-reperfusion is one of the most important factors thatcause the incidence of biliary complicance. The aim of thisstudy was to investigate the effects of ischemia reperfusionon epithelial cells apoptosis and proliferation of intrahepaticbile duct (IBD) (>20 μm).METHODS: 30-minute warm ischemia was applied to ratlivers respectively, and experiment was performed on days2,7, 14, 28 after reperfusion. Apoptosis was determined insitu by morphology and TUNEL, and cholangiocyte proli-feration was evaluated in situ by morphometry of liver sec-tions stained for cytokeratin-19 ( CK-19) and by prolifera-ting cellular nuclear antigen staining in liver sections.RESULTS: Two days after ischemia reperfusion, apoptosisof cells was observed in large intrahepatic bile ducts (>20μm) (5.6%±1.2%) , but the number of large intrahepaticbile ducts reduced (0.32 ±0.06). Seven days after ischemiareperfusion, the apoptosis index of cholangiocytes de-creased to 1.2%±0.3%, and the number of intrahepatic bileducts began to proliferate and returned to nearly normal onday 28.CONCLUSION: Ischemia reperfusion causes a decrease inthe number of intrahepatic bile ducts (>20 μm) as a resultof a higher rate of apoptosis and absence of initial prolifera-tion.