Discriminative pentobarbital stimulus in rats immediately after intravenous administration.
Rats with chronically implanted venous cannulas were trained to make differential active or passive shock-avoidance responses in a 2-compartment box at 15 sec after i.v. adminstration of pentobarbital (5 mg/kg) or saline. The discriminative pentobarbital stimulus persisted for several min after adminstration. The pentobarbital response also was elicited in tests at 15 sec after i.v. injection of chlordiazepoxide (2.5 and 5 mg/kg) or alcohol (500 mg/kg). Subsequent training at 10 min after i.p. injection of pentobarbital (10 mg/kg), followed by tests after i.p. administration of other drugs, indicated that the discriminative drug stimulus is qualitatively similar with this different route and time interval. A general preference for the passive over the active response developed only in the second stage of training, during i.p. injections.
D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects; D002707:Chlordiazepoxide / Q000494:pharmacology; D004193:Discrimination Learning / Q000187:drug effects; D004192:Discrimination, Psychological / Q000187:drug effects*; D000431:Ethanol / Q000494:pharmacology; D007274:Injections, Intraperitoneal; D007275:Injections, Intravenous; D008297:Male; D010424:Pentobarbital / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D013997:Time Factors
D000431:Ethanol; D002707:Chlordiazepoxide; D010424:Pentobarbital