Ischemic preconditioning protects the dog kidney from ischemia-reperfusion injury

Objective: To evaluate the effects of unilateral ischemic insult and ischemic preconditioning (IPC) on renal histology in a canine model. Methods: 30 dogs were randomized into 4 groups. In group A (5 male controls) and group B (5 female controls), ischemia was induced by clamping both left renal arteries for 40 min. Dogs in group C (10 male cases) or group D (10 female cases) underwent 5 min of arterial clamping and 10 min of declamping prior to the final 40-min ischemia induction. Renal biopsy was prepared 48 h later and microscopically examined. Results: The control groups (A and B) developed 40% frank necrosis, 60% moderate injury, and there was no intact renal tissue in this group with no difference between sexes. The IPC groups (C and D) revealed 55% moderate injury and 45% normal pathology; however, there was no frank necrosis among them. Better IPC protection in the female group was not statistically significant. Conclusion: An IPC schedule of 5-min ischemia and 10-min reperfusion improves ischemia-reperfusion injury from subsequent prolonged ischemia in a canine model.