Characterisation of the discriminative stimulus properties of flumazenil

Rats were trained to discriminate flumazenil (15 mg/kg i.p.) from vehicle in a two-lever, food-reinforced, operant conditioning procedure. Substitution tests were performed with a wide dose range of flumazenil and of several benzodiazepines and non-benzodiazepine compounds possessing behavioural effects similar to or opposite to those of benzodiazepine agonists. The results indicate that low doses of flumazenil have behavioural effects, that the flumazenil cue has a low degree of specificity and is most strongly related to the stimulus properties of benzodiazepines.