Time course of discriminative stimulus effects of bretazenil and chlordiazepoxide in rats.
The time course of the discriminative stimulus effects of a benzodiazepine partial agonist, bretazenil, and a benzodiazepine full agonist, chlordiazepoxide, were determined in rats after administration of two doses of either drug. As in man, bretazenil was considerably shorter-acting than chlordiazepoxide, with 0% drug-appropriate responding at the 2-h time point after the training dose of 7 mg/kg and < 20% drug-appropriate responding at 9 h after the 14 mg/kg dose. With chlordiazepoxide, responding on the water-appropriate lever did not occur in all rats until 7 h after administration of the training dose of 7 mg/kg, compared to 17 h after administration of 14 mg/kg. Although there was considerable individual variability with both drugs, it would appear that the drug discrimination procedure can be a valuable tool for studying the time course of the interoceptive effects of psychoactive drugs.
Bronson
M
M
Department of Pharmacal Sciences, Auburn University, AL 36849-5503, USA. Bronsme@mail.auburn.edu
Chen
H C
HC
D000818:Animals; D014151:Anti-Anxiety Agents / Q000494:pharmacology*; D000927:Anticonvulsants / Q000494:pharmacology*; D001570:Benzodiazepinones / Q000494:pharmacology*; D002707:Chlordiazepoxide / Q000494:pharmacology*; D004193:Discrimination Learning; D004192:Discrimination, Psychological / Q000187:drug effects*; D006993:Hypnotics and Sedatives / Q000494:pharmacology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
D014151:Anti-Anxiety Agents; D000927:Anticonvulsants; D001570:Benzodiazepinones; D006993:Hypnotics and Sedatives; D002707:Chlordiazepoxide; C054626:bretazenil