Isolation of a GABA receptor from bovine brain using a benzodiazepine affinity column

AbstractBenzodiazepine receptor solubilized from bovine cortical membranes was bound to a new benzodiazepine affinity column, the synthesis of which is described. Bio-specific elution with the benzodiazepine compound chlorazepate resulted in the elution of fractions highly enriched in specific binding for the GABA receptor agonist muscimol. Specific activity for [3H]muscimol binding was >1.3 nmol/mg protein. It is shown that [3H]flunitrazepam binding activity can be recovered by removal of chlorazepate from the purified fraction. These results strongly support a model which suggests that the 2 binding sites reside on the same physical entity