Picrotoxin-diazepam interaction in a behavioural schedule of differential reinforcement of low rates.

In rats working in a behavioural schedule of differential reinforcement of low rates (6 or 10 sec), picrotoxin (1 mg kg-1) decreased the number of premature responses and increased (in DRL 10 sec only) the number of rewarded responses. The effect of picrotoxin was antagonized by diazepam (2 mg kg-1). In contrast to picrotoxin, strychnine (1.5 mg kg-1) increased the number of premature responses.