Protective effect and mechanism of ischemic preconditioning on ischemic reperfusion injury of pancreas graft in the rat

Objective:To investigate the effect of ischemic preconditioning (IPC) on ischemic reperfusion (I/R) injury of pancreas graft in the rat, and analyze the possible mechanism.Methods: Thirty steptozozin (STZ)- induced diabetic SD rats were randomly assigned to 5 groups: Group N(n=6) suffer with sham operation, Group I/R consisted of 6 diabetic rats which received pancreas transplantation alone , Group IPC consisted of 18 diabetic rats received pancreas transplantation with 5 min ischemia and 5 min reperfusion once (IPC_1, n=6),twice (IPC_2, n=6) and thrice (IPC_3, n=6) before ablating donors. The blood glucose, NO and TNF-α in serum, MDA, SOD and MPO in pancreatic tissue were monitored before and after reperfusion. Results: ①The mean blood glucose level in Group IPC was lower than that in Group I/R; ②The mean NO and SOD level in Group IPC was higher than that in Group I/R, the mean TNF-α, MDA and MPO level in Group IPC was lower than that in Group I/R. Conclusion:①IPC can protect rat pancreas graft from I/R injury during pancreas transplantation alone, the possible mechanism may be increasing production of endogenous NO and SOD, relieving conglutination and aggregation of PMNs in pancreas and restraining synthesis of TNF-α. ② 5 min ischemia and 5 min reperfusion twice is the best way to induce IPC in rat pancreas graft .