Article date: 1985/6/24
PubMed ID: 2988708
Journal name: Brain research (ISSN: 0006-8993)
To support a postulated neurotransmitter character of gamma-aminobutyric acid (GABA) in the vertebrate vestibule, [3H]GABA binding was measured in a crude membrane preparation of chick inner ear ampullary cristae. In the absence of divalent cations bound [3H]GABA was displaced by unlabeled GABA, muscimol or bicuculline, but it was not displaced by (+/-)-baclofen. A single population of [3H]GABA binding sites with an equilibrium constant of 19.4 nM and a maximum binding capacity of 0.58 pmol/mg protein was found. These results suggest the possible existence of a synaptic GABAA receptor in the chick inner ear membranes and sustain the neurotransmitter role of GABA in the chick vestibule.
Author List: Meza G, González-Viveros M T, Ruiz M
Publication Types: Journal Article; Research Support, Non-U.S. Gov't
Substances mentioned in the article: Receptors, GABA-A; Muscimol; gamma-Aminobutyric Acid; Baclofen; Bicuculline;
Mesh terms: Animals; Baclofen/metabolism; Bicuculline/metabolism; Binding, Competitive; Chickens/metabolism; Male; Muscimol/metabolism; Receptors, GABA-A/analysis; Subcellular Fractions/metabolism; Vestibule, Labyrinth/metabolism; gamma-Aminobutyric Acid/metabolism;