The protective effects of ischemic postconditioning on renal ischemia-reperfusion injury in rats

Objective To investigate the effects of ischemic preconditioning and postconditioning on renal ischemia-reperfusion injury in rats.Methods Thirty male SD rats were randomly divided into four groups: sham group,ischemia/reperfusion(I/R) group,ischemia preconditioning group(I-Precon group: the right kidney was cut off;after three cycles of 5-minute ischemia and 2-minute reperfusion,the left kidney pedicle was blocked for 60 min and then reperfused for 4 h),and ischemia postconditioning group(I-Postcon group: the right kidney was cut off;the left kidney pedicle was blocked for 60 min;after six cycles of 10-second reperfusion and 10-second ischemia,it was then reperfused for 4 h).The blood urea nitrogen(BUN),creatinine(Cr) concentration,malondialdehyde(MDA) content and superoxide dismutase(SOD) activity were measured.The ischemic left renal tissue was collected for morphologic observation.Results Compared with those in I/R group,BUN,Cr and MDA concentrations decreased significantly(P0.05),while SOD activity increased in I-Precon and I-Postcon groups(P0.05).The morphologic result also showed that renal I/R injury attenuated obviously in I-Precon and I-Postcon groups.Moreover,I-Postcon had better protective effects on renal function and pathological injury than I-Precon.Conclusion Both ischemic preconditioning and postconditioning can attenuate renal ischemia-reperfusion injury in rats.The mechanism is partly related to the enhancement of antioxidation.