Immunohistochemical localization of N-methyl-D-aspartate receptor NR1, NR2A, NR2B and NR2C/D subunits in the adult mammalian cerebellum

The distributions of the N-methyl-D-aspartate (NMDA) receptor NR1, NR2A, NR 2B and NR2C/D subunits were mapped in adult mouse cerebellum using subunit- specific antibodies. Immunostaining with anti-NR1 antibodies was prominent in cell bodies and dendritic arbors of Purkinje cells, was light to moderat e in cerebellar granule cells, Golgi interneurons and interneurons in the m olecular layer. Anti-NR2A subunit-specific antibody staining of mouse cereb ellum was moderate in the granule cells, and moderate to dense in Purkinje neurons and Bergmann glia. However, Purkinje neurons were not immunolabelle d in adult rat brain. Anti-NR2B subunit-specific immunostaining was promine nt in Purkinje cell bodies and dendrites but absent from the granule cell l ayer. Anti-NR2C/D subunit-specific immunostaining was largely restricted to cerebellar granule cells. These studies reveal that NMDA receptor subunits display distinct but overlapping expression patterns in the adult mammalia n cerebellum. Furthermore, we have observed some differences between rats a nd mice in terms of the NMDA receptor subunits expressed in specific cerebe llar cell types. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved .