Comparative neuroprotective effects of pentobarbital, vinpocetine, flunarizine and ifenprodil on ischemic neuronal damage in the gerbil hippocampus.

We studied the protective effects of pentobarbital, vinpocetine, flunarizine, and ifenprodil on delayed neuronal death using Mongolian gerbils. The animals were allowed to survive for 7 days after 5 min of cerebral ischemia induced by bilateral occlusion of the common carotid arteries. Hippocampal cell loss was quantified histologically 7 days following ischemia. Intraperitoneal application of pentobarbital (40 mg/kg) 30 min and vinpocetine (50 and 100 mg/kg) 10 min before ischemia significantly reduced neuronal cell loss in the CA1 sector. However, the intraperitoneal administration of flunarizine (10 and 30 mg/kg) and ifenprodil (10 and 30 mg/kg) 15 min before ischemia was not protective. The results suggest that pentobarbital and vinpocetine prevent ischemic neuronal damage, but not flunarizine and ifenprodil. These findings are of interest in relation to the mechanism of delayed neuronal death.