Effects of clozapine, chlorpromazine and diazepam upon adjunctive and schedule controlled behaviors.
Two twelve-animal groups of rats were trained to press a lever for food reinforcement under either a fixed ratio 20 (FR 20) or a fixed interval 2 min (FI 2 min) schedule. During the FI 2 min schedule a measure of adjunctive behavior (i.e., drinking) was taken. Each group was then administered various doses of chlorpromazine (2.5, 5.0, 10.0 mg/kg, P.O.), clozapine (2.5, 5.0, 10.0 mg/kg, P.O.) or diazepam (5.0, 10.0, 15.0 mg/kg, P.O.) in a random order. All three drugs reliably reduced FR 20 response rates in a dose dependent manner, but chlorpromazine and clozapine were more potent in this regard. Chlorpromazine reduced FI 2 min responses rates especially in the terminal portions of the fixed intervals while diazepam generally elevated rates primarily in the min-portion of the interval. Clozapine produced a less defined effect on overall responding. All three drugs affected index of curvature. Only chlorpromazine was able to reliably reduce occurrence of adjunctive behavior and reinforcements.
D000818:Animals; D002746:Chlorpromazine / Q000494:pharmacology*; D003024:Clozapine / Q000494:pharmacology*; D003975:Diazepam / Q000494:pharmacology*; D003984:Dibenzazepines / Q000494:pharmacology*; D004327:Drinking Behavior / Q000187:drug effects*; D008297:Male; D051381:Rats; D012055:Reinforcement Schedule
D003984:Dibenzazepines; D003024:Clozapine; D003975:Diazepam; D002746:Chlorpromazine