CHARACTERIZATION OF THE BINDING OF [³H]MUSCIMOL, A POTENT γ‐AMINOBUTYRIC ACID AGONIST, TO RAT BRAIN SYNAPTOSOMAL MEMBRANES USING A FILTRATION ASSAY

Abstract

Abstract— The binding of [ 3 H]muscimol, a potent GABA agonist, to crude synaptic membranes prepared from rat brain was studied using a filtration method to isolate membrane‐bound ligand. Specific binding was found to be saturable and occurred to two binding sites of K d 5 5 and 30 n m . Binding was Na + ‐independent and enhanced by both freezing and Triton treatment. Regional and subcellular distribution studies and pharmacological characterization of specific [ 3 H]muscimol binding are consistent with binding to the synaptic GABA receptor.