The Effect Of Ischemic Postconditioning On The Injury Of Liver Function After Limb Ischemia Reperfusion In Rat

Objective: To observe the effect of ischemic postconditioning on the injury of liver function after limb ischemia reperfusion in rat and the potential mechanism. To compare the protective effects of ischemic postconditioning and ischemic preconditioning on liver.Methods: The developments of rat hind limb ischemia reperfusion model, 32 healthy male SD rats were randomly divided into shamoperated (SO), Ischemia-reperfusion (I/R),ischemic preconditioning(IPC)and ischemic postconditioning (IPo)groups. IPC was achieved by brief episodes of ischemia/repefusion applied prior to ischemia,while IPo was achieved by several brief episodes of reperfusion before the persistent reperfusion procedure. Then we observed the hepatic function and the quantity change of SOD,MDA and MPO in hepatic tissue.The expressions of Bcl-2 and Bax in hepatic tissue were measured. The apoptosis in hepatic tissue was assessed. The ultrastructures of mitochondria were observed by electron microscope.Results: Compared with I/R, the activity of plasma enzyme and the concentrations of MDA and MPO in hepatic tissue in IPC and IPo decreased sharply(P<0.05),while the concentrations of SOD increased significantly (P<0.05).Moreover,the expression of Bcl-2 was increased;the expression of Bax and the apoptotic index were reduced.The diference were statistically significant.the ultrastructures of mitochondria damage also relieved obviously(P<0.O5).The difference between IPo and IPC was not obvious(P>0.05)Conclusion: IPo has protective effects on the liver function after limb ischemia-reperfusion in rats. IPo can attenuate ischemia-reperfusion injury by reducing the superoxide radical generation and inhibit apoptosis in hepatic tissue by up-regulating Bcl-2 and down-regulating Bax.There was no obvious difference between the protective effects of ischemic posconditioning and ischemic preconditioning.