Effects of Dexmedetomidine on Renal Ischaemia Reperfusion Injury in Streptozotocin-Induced Diabetic Rats.

Objective: The aim of this study was to investigate the effects of dexmedetomidine before and after ischaemia in diabetic rat kidney ischaemia reperfusion (IR) injury in the experimental diabetic rat model.

Methods: Data belonging to 35 rats weighing between 250 and 300 g were analysed. Diabetes mellitus (DM) was induced using streptozotocin. Groups had bilateral renal vasculature clamped for 45 min ischaemia before clamps were removed, and 4 hours reperfusion was applied. Rats were divided into five groups: Group I or nondiabetic sham group (n=7), Group II or diabetic sham group (n=7), Group III or diabetic IR group (n=7), Group IV or diabetic IR+prophylactic Dex P (before ischaemia) (n=7) and Group V or diabetic IR+therapeutic Dex T (following reperfusion) (n=7). Dexmedetomidine was administered at a dose of 100 μg kg-1 intraperitoneally. Histomorphological and biochemical methods were used to assess the blood and tissue samples.

Results: The proximal tubule injury score in the control sham group was significantly lower than in other groups. The proximal tubule and total cell damage scores of the diabetic IR group were significantly higher than the diabetic IR+Dex T group, and no significant difference was detected in the diabetic IR+Dex P group. The biochemical parameters of the IR group were significantly increased compared to Groups I and II; however, there was no significant reduction in these parameters in the groups administered dexmedetomidine.

Conclusion: Although administration of dexmedetomidine after ischaemia in the diabetic rat renal IR model was found to be more effective on the histopathological injury scores compared to preischaemic administration, this study has not shown that dexmedetomidine provides effective and complete protection in DM.