Neuronal damage in the striatum following forebrain ischemia: lack of effect of selective lesions of mesostriatal dopamine neurons.

Transient periods of global cerebral ischemia lead to selective neuronal damage in the striatum. We investigated the effects of unilateral 6-hydroxydopamine lesions of the mesostriatal dopamine (DA) system on the density and distribution of neuronal necrosis in the rat striatum following ischemia induced by bilateral occlusion of the common carotid arteries combined with hypotension. After both 12 and 15 min of ischemia, which caused slight and extensive striatal damage, respectively, there was no difference in the density of neuronal necrosis in the striatum between DA-lesioned and sham-operated animals. We conclude that the DA system alone does not modulate injury following complete cerebral ischemia, but may contribute significantly to damage following conditions such as during hypoglycemia and incomplete cerebral ischemia.