Objective:To investigate the effects of exogenous vascular endothelial growth factor(VEGF)on hepatic ischemia/reperfusion injury in rats. Methods:Thirty normal male Sprague-Dawley rats were randomly divided into three groups:group A that was subjected to ischemia/reperfusion injury with intraperitoneal administration of VEGF(50 μg/300 g)30 min before ischemia;group B with the same injury followed by saline administration in the same manner,and group C with only anesthetization leparotomy without ischemia. Animals were killed at 6 hours after reperfusion. Routine assays were performed for testing the levels of alanine aminotransferase(ALT),aspartate aminotransferase(AST),lactate dehydrogenase (LDH),the activity of hepatic myeloperoxidase(MPO)and induced nitric oxide synthase (iNOS).The pathological changes in the liver were evaluated in hematoxylin and eosin(HE)stained sections. Results:The levels of serum ALT,AST,LDH and the activity of iNOS,MPO in hepatic tissues increased significantly after hepatic ischemia/reperfusion injury. But these effects were offset by administration of VEGF(P < 0.01). In group B,widespread pathological changes and cell apoptosis were observed in the hepatic tissue following hepatic ischemia/reperfusion injury,while similar changes were scarcely visible in groupe A due to the protective effect of intraperitoneal administration of VEGF 30 min before ischemia. Conclusion:The exogenous VEGF can depress the activity of iNOS and alleviate the liver function during the ischemia/reperfusion period,and protect the liver from ischemia and reperfusion injury.