Protective effect of nitric oxide on hepatic injury of limb ischemia preconditioning following limbs ischemia reperfusion in rats

Objective To evaluate the possible role of nitric oxide(NO) in the protective effect in limb ischemia preconditioning on hepatic injury following hind limbs ischemia reperfusion in rats.Methods Thirty-two male Wistar rats were divided into control group,limbs ischemia-reperfusion(LIR) group,limb ischemia preconditioning(IPC) group and L-NAME group,8 rats in each group.The bloodflow of double hindlimbs was not occluded in control group.The blood flow was occluded by rubber straps for 4 hours and restored reperfusion for 4 hours in LIR group.In IPC group,the blood flow was occluded for 5 minutes and restored for 5 minutes which was repeated four times in advance,the remaining operation was similar to LIR group.The operation was similar to IPC group in L-NAME group except an intravenous drip of L-NAME before restoring.The changes of NO,endothelin-1(ET-1),malondialdehyde(MDA),alanine transaminase(ALT) and aspartate transaminase(AST) in plasma were observed.The contents of NO,ET-1,MDA,myeloperoxide(MPO) and the ratio of DNA chain in liver were measured.Results Compared with control group,the levels of NO,ET-1,MDA,ALT,AST in plasma and the contents of NO,ET-1,MDA,MPO in liver increased(P0.05),the ratio of DNA chain in liver decreased in LIR group(P0.05);compared with IPC group,the levels of ET-1,MDA,ALT,AST in plasma and the contents of ET-1,MDA and MPO in liver increased(P0.05),NO in both plasma and liver and the ratio of DNA chain in liver decreased(P0.05).There was no significant difference in above indexes between L-NAME group and LIR group(P0.05).Conclusion NO perhaps participates the protection effect of LIR on hepatic injury following limbs ischemia reperfusion in rats,the possible role is related to restrain the action of ET-1,improving the aggregation of neutrophil and alleviating the damage of the lipid peroxidation.