RESUMEN
BACKGROUND AND OBJECTIVES: The aim of this study was to evaluate the effects of remote ischemic preconditioning by brief ischemia of unilateral hind limb when combined with dexmedetomidine on renal ischemia-reperfusion injury by histopathology and active caspase-3 immunoreactivity in rats. METHODS: 28 Wistar albino male rats were divided into 4 groups. Group I (Sham, n=7): Laparotomy and renal pedicle dissection were performed at 65th minute of anesthesia and the rats were observed under anesthesia for 130min. Group II (ischemia-reperfusion, n=7): At 65th minute of anesthesia bilateral renal pedicles were clamped. After 60min ischemia 24h of reperfusion was performed. Group III (ischemia-reperfusion+dexmedetomidine, n=7): At the fifth minute of reperfusion (100µg/kg intra-peritoneal) dexmedetomidine was administered with ischemia-reperfusion group. Reperfusion lasted 24h. Group IV (ischemia-reperfusion+remote ischemic preconditioning+dexmedetomidine, n=7): After laparotomy, three cycles of ischemic preconditioning (10min ischemia and 10min reperfusion) were applied to the left hind limb and after 5min with group III. RESULTS: Histopathological injury scores and active caspase-3 immunoreactivity were significantly lower in the Sham group compared to the other groups. Histopathological injury scores in groups III and IV were significantly lower than group II (p=0.03 and p=0.05). Active caspase-3 immunoreactivity was significantly lower in the group IV than group II (p=0.01) and there was no significant difference between group II and group III (p=0.06). CONCLUSIONS: Pharmacologic conditioning with dexmedetomidine and remote ischemic preconditioning when combined with dexmedetomidine significantly decreases renal ischemia-reperfusion injury histomorphologically. Combined use of two methods prevents apoptosis via active caspase-3.