The neuroprotective effects of combined nimodipine and superoxide dismutase on cerebral ischemia/reperfusion in rats

Objective To investigate the effects of the combination therapy of nimodipine with superoxide dismutase for reperfusion injury after focal cerebral ischemia in rats. Methods Forty-five adult male Wistar rats were randomly divided into 4 groups, nimodipine, superoxide dismutase, nimodipine plus superoxide dismutase and control groups. A rat model of middle cerebral artery occlusion (MCAO) was induced by the intraluminal suture method; Reperfusion was performed 4 hours after cerebral ischemia. At 20 minutes before reperfusion after cerebral ischemia, 12 h and 36 h after reperfusion, the medications were injected slowly into the tail veins of rats. The survival rate of rats was calculated 48 hours after cerebral ischemia/reperfusion, and the volumes of cerebral infarction and neurological deficit scores were measured. Results ① The survival rate of rats in the four groups were 41.7%, 27.3%, 70.0% and 25%, respectively. The survival rate in nimodipine plus superoxide dismutase group is higher than that in the control group (P0.05). ② Neurological deficit scores were 4.39±0.197, 4.47±0.492, 3.79±0.521 and 4.67±0.709, respectively. Neurological deficit scores in nimodipine plus superoxide dismutase group were less than those in the control group (P0.01) and the other two medication groups (P0.05). ③ Cerebral blood flow in rats was 96±23%, 81±19.457%, 129±47.053% and 79±40.533%, respectively. In comparison to the other medication groups, the nimodipine plus superoxide dismutase group has a higher cerebral blood flow (P0.05). ④ The volumes of cerebral infarction in rats were 261.20±55, 261.17±59, 128.53±58and 383.50±59mm3, respectively. The volumes of cerebral infarction in nimodipine plus superoxide dismutase group was less than control group (P0.05) and the other 2 medication groups (P0.01, P0.05, respectively). Conclusion The neuroprotective effects of combination of nimodipine and superoxide dismutase on focal cerebral ischemia/reperfusion injury in rats were better than the single of the two medications.