Benzodiazepine receptor binding: the interactions of some non-benzodiazepine drugs with specific [3H] diazepam binding to rat brain synaptosomal membranes.

The interaction of several non-benzodiazepine drugs with [3H] diazepam binding to benzodiazepine receptors in rat brain synaptosomal membranes was investigated. Baclofen, benzoctamine, hydroxyzine, chlorpromazine, haloperidol, imipramine, and amitriptyline displace specific [3H] diazepam binding, but the concentrations needed are too high to explain pharmacological effects of these drugs by an interaction with benzodiazepine receptors. The most potent non-benzodiazepine drug for inhibiting specific [3H] diazepam binding was methaqualone (IC50 value of 150 micrometer). It is suggested that interactions with benzodiazepine receptors may account for the anxiolytic and anticonvulsive side effec…