RESUMO
OBJECTIVE: Ischemia/reperfusion (I/R) injury is a major cause of acute organ dysfunction and I/R related acute renal failure is a common clinical problem. Diabetes mellitus is defined as a risk factor for the development of acute renal injury as diabetic nephropathy compromises the renal tolerance to ischemia. The aim of this study was to investigate the protective effect of magnesium sulfate in a diabetic rat renal I/R injury model. MATERIALS AND METHODS: Diabetes mellitus was induced using streptozotocin. Thirty-five rats were divided into five groups: Group I: Nondiabetic sham group; Group II: Diabetic sham group; Group III: Diabetic I/R group; Group IV: Diabetic I/R + prophylactic (preischemic) MgSO4; and Group V: Diabetic I/R + therapeutic (following reperfusion) MgSO4 group. MgSO4 was administered 200 mg/kg intraperitoneally. Renal I/R (45 min ischemia + 4 h reperfusion) was induced in both kidneys. Histomorphological, immunohistochemical (caspase-3 and iNOS) and biochemical (BUN, Creatinine) methods were performed to assess the blood and tissue samples. RESULTS: Histomorphological injury scores and immunostaining intensities (for both caspase-3 and iNOS) were significantly lower in the MgSO4 administered groups (prophylactic and therapeutic) than in the Diabetic IR group. There were no significant differences in biochemical parameters (BUN, Cr) between the MgSO4 administered groups and the Diabetic IR group. CONCLUSIONS: In the present study, it was demonstrated by histomorphological and immunohistochemical methods that magnesium sulfate administration before ischemia or following reperfusion significantly reduced renal I/R injury in a diabetic rat model.
