Characterization of [3H]muscimol binding to mouse brain membranes

摘要: Abstract The binding of [ 3 H]muscimol {[methylene- H(N)]-3-hydroxy-5-aminoethyl isoxazole} to a membrane fraction from mouse brain was studied as possible model for the GABA recognition site γ-aminobutyric acid (GABA)-anionophore receptor complex. Kinetic studies showed two distinct association and dissociation rate constants, 2.3 × 10 −4 1.4 −5 sec −1 nM 1.2 −2 1.0 −3 dissociation. Equilibrium analysis (Scatchard plot) data also indicated types sites with K D equal 9 −9 70 M. Detergents (0.1% Triton X-100, 0.1% Lubrol PX or 5% Tween 20) had no effect on other conformationally restricted agonists such imidazoleacetic acid, isoguvacine, THIP (4,5,6,7-tetrahydroisoxazole [5,4-c] pyridine-2-ol), (±)-isonipecotic acid. In contrast this, detergents potentiated ability less β-alanine in displacing H]muscimol. Binding bicuculline reduced by all detergent treatments.