title: Localization of a G-protein-coupled inwardly rectifying K+ channel, CIR, in the rat brain.
abstract: The cellular localization of a G-protein-coupled K+ channel, CIR, in the rat brain has been demonstrated using a CIR-specific antibody, in combination with in situ hybridization. The CIR protein and messenger RNA were found in the cerebellar cortex, hippocampal formation, olfactory system, cerebral cortex, basal ganglia, several nuclei of the lower brain stem and the choroid plexus. In contrast to the messenger RNA, which was concentrated in the cell soma, the CIR protein was found in a subset of nerve fibers and, in other cases, in axon terminals. In the cerebellar cortex and hippocampus, the CIR protein was concentrated in the axon terminals of basket cells which are known to be GABAergic interneurons. This discrepancy between the distribution of protein and messenger RNA was observed in the substantia nigra, the interpeduncular, trigeminal, hypoglossal, oculomotor and red nuclei of the lower brain stem, and the tufted and mitral cells of the olfactory bulb. These observations suggested the translocation of the CIR protein into the nerve fibers following synthesis in the cell soma. Furthermore, its specific neuronal localization, especially in GABAergic interneurons, suggested the importance of CIR in synaptic transmission in neuronal systems.
authors.affiliation: Department of Molecular and Cellular Biology, Nippoa Boehringer Ingelheim Co., Ltd, Kawanishi Pharma Research Inst., Japan.
authors.forename: M
authors.initials: M
authors.lastname: Iizuka
authors.forename: I
authors.initials: I
authors.lastname: Tsunenari
authors.forename: Y
authors.initials: Y
authors.lastname: Momota
authors.forename: I
authors.initials: I
authors.lastname: Akiba
authors.forename: T
authors.initials: T
authors.lastname: Kono
mesh_terms: D000818:Animals; D001479:Basal Ganglia / Q000737:chemistry / Q000166:cytology; D001923:Brain Chemistry; D001933:Brain Stem / Q000737:chemistry / Q000166:cytology; D002531:Cerebellum / Q000737:chemistry / Q000166:cytology; D002540:Cerebral Cortex / Q000737:chemistry / Q000166:cytology; D002831:Choroid Plexus / Q000737:chemistry / Q000166:cytology; D051676:G Protein-Coupled Inwardly-Rectifying Potassium Channels; D019204:GTP-Binding Proteins / Q000502:physiology*; D006624:Hippocampus / Q000737:chemistry / Q000166:cytology; D015151:Immunoblotting; D017403:In Situ Hybridization; D007395:Interneurons / Q000737:chemistry; D008297:Male; D009830:Olfactory Bulb / Q000737:chemistry / Q000166:cytology; D015221:Potassium Channels / Q000032:analysis / Q000235:genetics*; D024661:Potassium Channels, Inwardly Rectifying; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D011976:Receptors, Muscarinic / Q000032:analysis / Q000235:genetics*; D005680:gamma-Aminobutyric Acid / Q000502:physiology
chemical_list: D051676:G Protein-Coupled Inwardly-Rectifying Potassium Channels; D015221:Potassium Channels; D024661:Potassium Channels, Inwardly Rectifying; D012333:RNA, Messenger; D011976:Receptors, Muscarinic; D005680:gamma-Aminobutyric Acid; D019204:GTP-Binding Proteins