The effects of surgical and chemical lesions on striatal [formula omitted] binding: Correlation with [ 3H]dopamine uptake

Abstract

The specific binding of [ 3 H] threo-(±)- methylphenidate to membranes prepared from rat striatum was significantly reduced following either surgical lesions of the medial forebrain bundle or intracerebroventricular administration of 6-hydroxydopamine. The decrease in the density of [ 3 H] threo-(±)- methylphenidate binding sites in striatum following chemical or surgical denervation was highly correlated with the decrease in [ 3H]dopamine uptake. In contrast, intracerebroventricular administration of 5,7-dihydroxytryptamine, AF64A, or chronic parenteral administration of reserpine did not alter either the number or apparent affinity of [ 3 H] threo-(±)- methylphenidate binding sites. These data suggest that the specific binding sites for [ 3 H] threo-(±)- methylphenidate in striatum are localized to dopaminergic nerve terminals, and may be associated with the dopamine transport complex.