Differential antagonism of the anticonflict effects of typical and atypical anxiolytics.

Selected benzodiazepine and non-benzodiazepine agents were studied alone or in the presence of benzodiazepine antagonists in the shock-induced suppression of drinking (SSD) procedure in rats. The disinhibitory activity of chlordiazepoxide, CL218,872, zopiclone and CGS 9896 was antagonized by two benzodiazepine antagonists, RO-15-1788 and CGS 8216. In contrast, the disinhibitory activity of fenobam, meprobamate, phenobarbital and tracazolate was not antagonized by either RO 15-1788 and CGS 8216. From these data it is apparent that the anticonflict activity of agents that bind to benzodiazepine receptors is blocked by benzodiazepine antagonists. In contrast, the activity of anxiolytics that are not displacers are unaffected even at higher doses.