AIM: To investigate the changing patterns of glycogen and enzyme histochemical activities in rat liver graft under a dif ferent warm ischemia time (WIT) and to predict the tolerant time limitation of the liver graft to warm ischemia injury.METHODS: The rats were randomized into five groups, WTT was 0, 15, 30, 45, 60 min, respectively, and histochemical staining of liver graft specimens was observed. The recovery changes of glycogen and enzyme histochemistry activities were measured respectively 6 and 24 h following liver graft implantation.RESULTS: The activities of succinic dehydrogenase, cytochrome oxidase, apyrase (Mg++-ATPase) and content of glycogen were decreased gradually after different WIT in a time-dependent manner. The changes were significant when WIT was over 30 min.CONCLUSION: Hepatic injury is reversible within 30 min of warm ischemia injury. Glycogen and enzyme histochemistry activities of liver grafts and their recovery potency after reperfusion may serve as criteria to evaluate the quality of liver grafts.