Autoradiographic localization of cerebellar excitatory amino acid binding sites in the mouse

Abstract

We have investigated the cellular localization of cerebellar excitatory amino acid binding sites in normal mice, in mice deficient in granule cells and, perhaps, stellate, basket and Golgi cells (granuloprival mice) and in mice lacking Purkinje cells. In the molecular layer of normal mouse cerebellum, the quisqualate-sensitive binding sites were the predominant type of excitatory amino acid receptor and there were relatively few N-methyl--aspartate or kainate-sensitive binding sites. The granule cell layer of normal mice contained a mixture of all 3 types, the N-methyl--aspartate-sensitive binding sites being predominant.In the molecular layer of granuloprival mice, the number of quisqualate-sensitive binding sites was increased to 214% of control (P P P P P In the molecular layer of mice lacking Purkinje cells, quisqualate-sensitive binding sites were reduced to 29% (P These results suggest that (1) quisqualate-sensitive binding sites are located principally on dendrites of Purkinje cells and that they up-regulate after deafferentation; (2) N-methyl--aspartate-sensitive binding sites are located on granule cells and, perhaps, stellate, basket and Golgi cells, and (3) kainate binding sites are located on cell bodies of granule and, perhaps, Golgi cells.