The effects of atorvastatin and ischemic postconditioning on hepatic ischemic-reperfusion injury in rats

Objective To compare the protective effect of atorvastatinandischemic postconditioning on liver and the possible mechanisms during the hepatic ischemia-reperfusion injury.Methods Twenty-eight healthy male SD rats were randomly divided into 4 groups,namely control group(N),ischemia-reperfusion group(IR),ischemic postconditioning group(IPO) and atorvastatin preconditioning group(APC),each consisting of 7 rats each.Single liver 70% ischemia-reperfusion rats model was established.After the last reperfusion,blood was collected in each group from the superior and inferior vena cava of liver to detect alanine arninotransferase(ALT) and asparate aminotransferase(AST).Liver homogenate was centrifuged at low temperature,and the content variation of total superoxide dismustase(TSOD),malondialdehyde(MDA),myeloperoxidase(MPO),nitric oxide(NO) and nitrieoxidesynthas(NOS) in liver tissue were measured.Meanwhile,liver tissue section was observed under light microscope.Results After 45 minutes' ischemia followed by reperfusion for 90 minutes,it's obvious that the normal liver function was impaired,antioxidant enzyme activity decline and the large areas of necrosis in liver tissue were observed.In ischemic postconditioning group and atorvastatin group,the degree of hepatic ischemia-reperfusion injury was significantly reduced while the activity of SOD was increased and the levels of MDA,MPO as well as internal NO were decreased.Meanwhile,the injury of hepatic sinusoid epithelium and vascular endothelial was significantly reduced;so were the injury of liver cells and the Infiltration of Inflammatory cells.Conclusion Both IPO and atorvastatin have similar protective effect on hepatic ischemia-reperfusion injury.Atorvastatin required easier treatments.It's possible mechanisms include activating antioxidant free radicals,improving theability of organisms inscavenging oxygen free radicals,and enhancing anti-inflammatory effects.