PREVENTION OF ABNORMAL CALCIUM ACCUMULATION IN POSTISCHEMIC GERBIL BRAIN BY VINCONATE

We investigated the effect of vinconate on ischemia-induced calcium accumulation in the gerbil brain. The animals were allowed to survive for 7 days after 10 min of ischemia. Abnormal calcium accumulation was evaluated in the gerbil brain after ischemia. Following 10 min ischemia, abnormal calcium accumulation was found in the neocortex, the striatum, the hippocampus, the thalamus, the substantia nigra and the inferior colliculus. Intraperitoneal administration of vinconate (100 mg/kg) immediately after 10 min of ischemia significantly reduced the areas of abnormal calcium accumulation only in the striatum. However, the application of vinconate (100 and 300 mg/kg) 10 min before ischemia dose-dependently decreased the areas of abnormal calcium accumulation in the striatum, the thalamus and the substantia nigra. Morphological observation revealed neuronal damage in the identical sites of the abnormal calcium accumulation. Furthermore, a autoradiographic study using C-14-vinconate showed that this drug easily penetrates the blood-brain barrier and especially localizes in the striatum and the thalamus after 5 min ischemia. The result suggests that vinconate reduces the areas of abnormal calcium accumulation in the postischemic gerbil brain. This effect seems to be mediated via the hight distribution in the brain following ischemia.