The effects of remote ischaemic preconditioning and Dexmedetomidine in rat renal ischaemia reperfusion injury model

Background: Ischaemia reperfusion (IR) injury which can develope after shock, renal transplantation, urological procedures as partial nephrectomy, cardiopulmonary bypass and sepsis may result in severe organ failures. Remote ischaemic preconditioning (RIP) and pharmacological postconditioning are the effective methods that can be used to prevent IR injury. The aim of this study was to evaluate the effects of RIP and dexmedetomidine as pharmacological postconditioning in the rat renal IR injury model.Materials and Methods: After obtaining approval from the Instutional Ethics Committee, 28 Wistar albino male rats weighing approximately 250-300 g were divided into 4 groups. Laparotomy and renal pedicle dissection were performed to all groups under general anaesthesia. Group I (Sham, n=7): Laparotomy and renal pedicle dissection were performed and the rats were observed under anaesthesia without any intervention. Group II (IR, n=7): After laparotomy and 45 minutes of left renal pedicle occlusion, 4 hours of reperfusion was performed. Group III (IR+Dexmedetomidine, n=7): After laparotomy and while IR was being applied to left kidney, dexmedetomidine was administrated intraperitoneally (100?g/kg -approx.0.5-0.6 mL) at the fifth minute of reperfusion. Group IV (RIP+IR, n=7): Under anaesthesia, three cycles of ischaemic preconditioning (10 min ischaemia and 10 min reperfusion) were applied to the left hind leg and after five minutes, renal IR was performed. Durations of anaesthesia were equal in all groups. All the rats were sacrificed after the left kidney was processed for conventional histomorphology. Results: The total histomorphological renal injury score was significantly lower in the Sham group compared with the other groups (p< 0.01). The total renal injury score of IR group was significantly higher than the IR+Dexmedetomidine and RIP+IR groups (p< 0.01). There was no significant difference in total renal injury scores between the Dexmedetomidine and RIP groups (p=0,89).Conclusions: In the present study, it was demonstrated histomorphologically that both Dexmedetomidine and RIP decreased renal IR injury significantly in this experimental model ; but, no significant difference was found between Dexmedetomidine and RIP groups.Key words: Kidney, reperfusion injury, ischaemic preconditioning, dexmedetomidine