title: Antagonism by 8-OH-DPAT, but not ritanserin, of catalepsy induced by SCH 23390 in the rat.
abstract: In the present experiments, it was shown that the catalepsy induced by the dopamine D1 antagonist SCH 23390 (0.2 mg kg-1 sc), was completely antagonised by the administration of 8-OH-DPAT (0.1 mg kg-1 sc) for the duration of the effect of SCH 23390 (approx. 120 min). Neither the catalepsy induced by raclopride (16 mg kg-1 sc) nor that induced by SCH 23390 (0.2 mg kg-1 sc) could be antagonised by treatment with the 5-HT2 receptor antagonist ritanserin (0.13-2.0 mg kg-1 sc). Administration of SCH 23390 (0.0125-0.2 mg kg-1 sc) produced a significant suppression of avoidance behavior at all doses, and also produced a significant decrease in the number of intertrial crosses. At the higher doses, 0.05 and 0.2 mg kg-1 sc, there were also escape failures. In contrast to the finding in our previous report that raclopride and 8-OH-DPAT in a synergistic manner produce a suppression of conditioned avoidance behavior, no such interaction was found between 8-OH-DPAT (0.1 mg kg-1 sc) and SCH 23390 (6 micrograms kg-1 sc) in the present study.
authors.affiliation: Department of Psychology, University of Stockholm, Sweden.
authors.forename: M L
authors.initials: ML
authors.lastname: Wadenberg
mesh_terms: D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000494:pharmacology*; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects; D001552:Benzazepines / Q000037:antagonists & inhibitors*; D002375:Catalepsy / Q000139:chemically induced / Q000517:prevention & control*; D065127:Dopamine D2 Receptor Antagonists; D008297:Male; D020891:Raclopride; D051381:Rats; D017207:Rats, Sprague-Dawley; D016713:Ritanserin / Q000494:pharmacology*; D012457:Salicylamides / Q000494:pharmacology
chemical_list: D001552:Benzazepines; D065127:Dopamine D2 Receptor Antagonists; D012457:Salicylamides; D016713:Ritanserin; D020891:Raclopride; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin