Neuron
Volume 3, Issue 3, September 1989, Pages 327-337
Journal home page for Neuron

Article
Two novel GABAA receptor subunits exist in distinct neuronal subpopulations

https://doi.org/10.1016/0896-6273(89)90257-2Get rights and content

Abstract

Two cDNAs encoding novel GABAA receptor subunits were isolated from a rat brain library. These subunits, γ2 and δ, share approximately 35% sequence identity with α and β subunits and form functional GABA-gated chloride channels when expressed alone in vitro. The γ2 subunit is the rat homolog of the human γ2 subunit recently shown to be important for benzodiazepine pharmacology. Cellular localization of the mRNAs encoding the γ2 and δ subunits in rat brain revealed that largely distinct neuronal subpopulations express the two subunits. The δ subunit distribution resembles that of the high affinity GABAA receptor labeled with [3H]muscimol; the γ2 subunit distribution resembles that of GABAA/benzodiazepine receptors labeled with [3H]flunitrazepam. These findings have implications for the composition of two different GABAA receptor subtypes and for information processing in networks using GABA for signaling.

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