RESUMEN
The mechanisms involved in brain neuronal damage in ischemia are related to the elevation of cytosolic calcium concentration and calcium antagonist is considered as a promising drug that may alleviate ischemic neuronal damage. Using transient global ischemia model of Mongolian gerbil, we studied the effect of nimodipine, a cerebroselective calcium antagonist, on ischemic brain edema. We treated each gerbil intraperitoneally with nimodipine (lmg/kg) or the same amount of saline 30 minutes prior to ischemia, and transient global ischemia was induced by means of clipping both common carotid arteries either for 10 minutes or for 45 minutes. Three hours after reperfusion, the animals were decapitated and the water content of the bain was determined by oven dry method. With 10 minute ischemia the brain water content in nimodipine pretreatment group (78.6 +/- 0.2%) was lower than that in saline pretreatment group (79.1 +/- 0.4%) significantly (p<0.05). But with 45 minute ischemia nimodipine pretreatment did not reduce the postischemic increase of water content compared with saline pretreatment (79.8 +/- 0.4% and 79 6 +/- 0.4%, respectively; not significant). Our results suggest that nimodipine pretreatment may suppress the development of ischemic brain edema and its effect depends largely on the extent of brain ischemia.