The differential expression pattern of the mRNAs encoding beta subunits (beta 1, beta 2, and beta 3) of GABAA receptor in rat brain.

Abstract

Gamma-aminobutyric acid (GABA) is a well known major inhibitory neurotransmitter in the vertebrate brain. Its inhibitory action is mediated through the activation of the specific receptors: the GABAA and GABAB receptors. Binding of GABA with GABAA receptor (GABAA-R) causes the chloride channel to open (for reviews see Roberts, 1986; Stephenson, 1988). Recent molecular cloning analysis has revealed that GABAA-R in the brain has at least five subunits and each subunit is consisted of several variants: α 1–5, β 1–3, γ 1–2, δ, and ε (Schofield et al., 1987; Levi tan et al., 1988; Richards et al., 1989; Schofield, 1989; Shivers et al., 1989; Ymer et al., 1989a, b). On the other hand, there is much evidence suggesting the heterogeneity of GABAA-R in the brain. For example, using specific oligonucleotide probes for α 1, α 2 or α 3 subunit mRNAs, Wisden et al. (1988) have revealed that the neurons expressing α 1 and α 2 subunit mRNAs are most abundant in layers II–IV of the bovine frontal cortex, while those expressing α 3 subunit mRNA are most abundant in layers V and VI. In addition, recent investigation by Ymer et al.KeywordsGABAA ReceptorGlobus PallidusVestibular NucleusPiriform CortexSubunit mRNAThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.