TY - JOUR T1 - Studies on the Relationship of γ-Aminobutyric Acid-Stimulated Diazepam Binding and the γ-Aminobutyric Acid Receptor JF - Molecular Pharmacology JO - Mol Pharmacol SP - 16 LP - 21 VL - 20 IS - 1 AU - PAUL J. MARANGOS AU - ANDREA M. MARTINO Y1 - 1981/07/01 UR - http://molpharm.aspetjournals.org/content/20/1/16.abstract N2 - The three binding parameters [3H]muscimol binding, [3H]diazepam binding, and γ-aminobutyric acid (GABA)-stimulated [3H]diazepam binding are compared in various brain areas and in response to various protein and membrane modifying reagents. Comparison of rat forebrain and cerebellum revealed a much higher ratio of [3H]muscimol- to [3H]diazepam-binding sites in cerebellum and less GABA-stimulated [3H]diazepam binding. Both sulfhydryl reducing and alkylating agents reduced [3H]muscimol binding (decreased binding affinity), and increased GABA-stimulated [3H]diazepam binding. Triton X-100-treated membranes display an increase in both the number and affinity of [3H]muscimol-binding sites, no change in basal [3H]diazepam binding, and a decrease in GABA-stimulated [3H]diazepam binding. The observed relationship between [3H]-muscimol-binding sites and the degree of GABA-stimulated [3H]diazepam binding suggests that the high affinity muscimol-binding site is not mediating the GABA enhancement effect. ER -