CELLULAR-DISTRIBUTION OF THE RAT D-1B RECEPTOR IN CENTRAL-NERVOUS-SYSTEM USING ANTIRECEPTOR ANTISERA

Polyclonal antisera have been generated against two unique polypeptide fragments in the rat D-1B dopamine (DA) receptor, as deduced from the cDNA sequence. Antisera titers were monitored using solid-phase ELISA . Once the titers were established, antisera specificity was determine d using Chinese Hamster ovary (CHO) cells, stably transfected with the full-length cDNA for the rat D-1B DA receptor. Immunoreactivity follo wing staining with either anti-D-1B DA receptor antisera was equivalen t, selective for the D-1B DA receptor-transfected CHO cells, and expre ssed at their membrane and within the cell cytoplasm. Minimal immunofl uorescent staining for D-1B DA receptor proteins was detected in untra nsfected CHO cells, or in D-1A DA receptor-transfected CHO cells. The regional and cellular distribution patterns for the D-1B DA receptor s ubtype were examined in various brain areas and illustrated significan t protein levels within the frontal and parietal cortices and in the h ippocampus and dentate gyrus. Lesser amounts of receptor protein stain ing were seen in the dorsal striatum, olfactory tubercle, and cerebell ar vermis. D-1B DA receptor protein staining was correlated with the c ellular expression of D-1B DA receptor mRNA transcripts in these same brain regions using concurrent fluorescent analyses. The homologous co incidence in staining patterns for the D-1B DA receptor transcripts an d encoded proteins in identified neurons of the frontal cortex and str iatum showed variations in receptor expression in these identified bas al ganglia pathways.