[Effect of the GABA receptor blockader bicuculline on the action of fenibut and diazepam].

Fenibut (100 mg/kg) suppressed the motility and emotional reactivity but did not possess any antiaggressive properties, whereas diazepam (2.5 mg/kg) did increase the motility and reduced aggressiveness in rats. Bicuculline (1.25 mg/kg) itself did not cause any behavioral changes, although it was capable of antagonizing the effects of diazepam and to potentiate those of fenibut. Bicuculline attenuated the GABA rise but did not influence the increased content of HVA and DOPAC after fenibut. The importance of the bicuculline-insensitive mechanisms in the action of fenibut and bicuculline-sensitive ones in the action of diazepam is discussed.