title: GABAA receptor subunit messenger RNAs show differential expression during cortical development in the rat brain.
abstract: Developmental changes of the expression of various GABAA receptor subunits (alpha 1, alpha 3, alpha 4, beta 1-3, and gamma 2) were examined in the fetal rat cerebral cortex using in situ hybridization histochemistry. The subunits showed three main patterns of development. The alpha 1 subunit showed the first pattern, in which no expression was observed during embryonic development. The alpha 4 and beta 1 subunits showed the second pattern, in which expression was observed in both the undifferentiated neuroepithelium and the developing cortical layers. The alpha 3, beta 2, beta 3, and gamma 2 subunits showed the third pattern, in which expression was only seen in the developing cortical layers. These findings strongly suggest the following: (i) the alpha 1 subunit is involved in GABAergic transmission in the mature cerebral cortex; (ii) the alpha 4 and beta 1 subunits are involved in both the differentiation of the neuroepithelium and the development of the cortical plate, and (iii) the alpha 3, beta 2, beta 3, and gamma 2 subunits are involved in the development of the cortical plate. Subunits already expressed on embryonic day 13 (beta 1, beta 3, and gamma 2) appear especially likely to have a special role in neuronal development.
authors.affiliation: Department of Anatomy and Neuroscience, Osaka University Medical School, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Araki
authors.forename: H
authors.initials: H
authors.lastname: Kiyama
authors.forename: M
authors.initials: M
authors.lastname: Tohyama
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D001923:Brain Chemistry / Q000502:physiology*; D002540:Cerebral Cortex / Q000033:anatomy & histology / Q000254:growth & development* / Q000378:metabolism; D005260:Female; D006651:Histocytochemistry; D017403:In Situ Hybridization; D009841:Oligonucleotides; D011247:Pregnancy; D012333:RNA, Messenger / Q000096:biosynthesis*; D051381:Rats; D017208:Rats, Wistar; D011963:Receptors, GABA-A / Q000096:biosynthesis*
chemical_list: D009841:Oligonucleotides; D012333:RNA, Messenger; D011963:Receptors, GABA-A