Effects of amrinone on bilateral renal ischemia/reperfusion injury.

Renal ischemia/reperfusion injury could arise as a consequence of clinical conditions such as renal transplantation, shock, cardiac arrest, hemorrhage and renal artery surgery. In this experimental study, we aimed to determine the preventive effects of amrinone on bilateral renal ischemia/reperfusion injury in rats. A total of 60 Wistar-albino rats were divided into six groups ( n=10). Midline laparotomies were made under ketamine anesthesia. In the sham, amrinone1 and amrinone2 without ischemia (AWI1 and AWI2) groups saline, 5 and 10 mg/kg of amrinone was infused, respectively. In the ischemia, ischemia plus amrinone1 (IPA1) and ischemia plus amrinone2 (IPA2) groups, saline and 5 and 10 mg/kg of amrinone was infused, respectively, at the beginning of reperfusion, subsequent to 45 min of bilateral renal artery occlusion. Following 6 h of reperfusion, blood was drawn to study serum BUN and creatinine and a bilateral nephrectomy was done to determine tissue malonyldialdehyde ( MDA) and myeloperoxidase (MPO) levels. The results were analysed by Mann-Whitney U-test. The parameters studied were statistically higher in the ischemia group compared with the other groups ( P<0.05 for each comparison), indicating renal I/R injury. These parameters were lower in the amrinone without ischemia groups (AWI1 and AWI2) than in the sham group, however there were no significant differences between the groups ( P>0.05, for each comparison). The treatment groups IPA1 and IPA2 had statistically similar results compared with the sham group, showing the preventive effect of amrinone on renal I/R injury at the given doses. We conclude that amrinone prevented experimental renal ischemia/reperfusion injury in rats, independently of the administered doses. This preventive effect of the agent could depend on its effect of regulating the microcirculation, in decreasing intracellular calcium and in preventing neutrophil activation. We propose that this preventive effect of amrinone - which has gained clinical application especially in cases of cardiac insufficiency - could also be exploited in clinical conditions related with renal ischemia/reperfusion.