Inhibition of [3H]Diazepam and [3H]3‐Carboethoxy‐β‐Carboline Binding by Irazepine: Evidence for Multiple “Domains” of the Benzodiazepine Receptor

Abstract
The binding of [3H]diazepam and [3H]3-carboethoxy-β-carboline was examined in rat brain synaptosomal membranes treated with irazepine, an alkylating benzodiazepine. Under incubation conditions that resulted in a 25–33% reduction in the Bmax of [3H]diazepam binding, only modest (max of [3H]3-carboethoxy-β-carboline were observed. The differential effects of irazepine on the binding of these two compounds may be explained by the presence of multiple areas or “domains” on the benzodiazepine receptor.