THE BENZODIAZEPINE - GABA - CHLORIDE IONOPHORE RECEPTOR COMPLEX - COMMON SITE OF MINOR TRANQUILIZER ACTION

Abstract

The demonstration of specific recognition sites for benzodiazepines in the mammalian CNS has altered current thinking on the mechanisms of action of the benzodiazepines and the neurochemical events which are associated with anxiety. Apparently the physiological regulation of the rat benzodiazepine receptor is far more complex than initially believed and includes a functional coupling to a GABA receptor and an associated chloride ionophore. It now appears that a number of other psychopharmacologic agents, including minor tranquilizers other than the benzodiazepines and several convulsants and anticonvulsants, may exert their pharmacologic effects by affecting 1 or more regulatory sites on the benzodiazepine receptor complex. In addition to a number of drugs, at least 1 endogenous small MW compound that has been isolated from the crude synaptosomal fraction of bovine cerebral cortex also appears to modulate this receptor complex. Drugs used were: diazepam; pentobarbital; meprobamate; pentylenetetrazol; R05-3663; 1,3-dihydro-5-methyl-2H-1,4-benzodiazepine-2-one.