Nitrendipine and superoxide dismutase in ischemic renal injury.

The effect of the Ca entry blocker nitrendipine, the antioxidant superoxide dismutase (SOD), and a combination of nitrendipine and superoxide dismutase on postischemic renal function was studied in four groups (n = 24) of rats. The rats in group 1 (n = 6) were the ischemic control and received 10 mL of 0.9% NaCl. Group II (n = 6) received SOD 7.0 mg/kg. Group III (n = 6) received nitrendipine 1 mg/kg. Group IV (n = 6) received nitrendipine 1 mg/kg and SOD 7 mg/kg. After administration, both kidneys were rendered ischemic by cross-clamping the renal vessels for 60 min. Comparison of 24-h creatinine clearance (CCr) for 3 days after reversal of ischemia revealed: (a) nitrendipine alone was the most effective in preserving renal function (p < .05); (b) SOD provided some degree of improvement, but only on day 3 (p < .05); (c) a similar result was detected using a combination of nitrendipine and SOD (p < .05); (d) there was no significant difference between SOD and nitrendipine nor between SOD and the combination of nitrendipine/SOD; (e) there was a significant improvement with nitrendipine when compared to the combination of nitrendipine/SOD (p < .05).