title: Polymodal dose-response curve for oxytocin in the social recognition test.
abstract: Available data concerning the effect of oxytocin on memory are often inconsistent. In the present study it was found that oxytocin, intracerebroventricularly injected to adult male rats in a dose range of 1 fg-10 ng/rat immediately after a 5-minute encounter with a juvenile, significantly reduces the social investigation time of the adult rat towards the same juvenile during a second encounter (120 min later) with two peaks of activity, at 10 fg and 1 ng/rat. Larger doses of oxytocin were ineffective. The oxytocin antagonist d(CH2)5Tyr(Me)-Orn8-vasotocin, injected 5 min before oxytocin by the same route and at the same doses, while being ineffective per se, completely abolished the memory-improving effect of a low dose of oxytocin (1 ng/rat) and, on the other hand, turned into memory-improving the effect of a high dose of oxytocin (500 ng/rat).
authors.affiliation: Department of Biomedical Sciences, University of Modena, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Benelli
authors.forename: A
authors.initials: A
authors.lastname: Bertolini
authors.forename: R
authors.initials: R
authors.lastname: Poggioli
authors.forename: B
authors.initials: B
authors.lastname: Menozzi
authors.forename: R
authors.initials: R
authors.lastname: Basaglia
authors.forename: R
authors.initials: R
authors.lastname: Arletti
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D007276:Injections, Intraventricular; D008297:Male; D008570:Memory, Short-Term / Q000187:drug effects; D010121:Oxytocin / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D012919:Social Behavior; D014668:Vasotocin / Q000031:analogs & derivatives / Q000494:pharmacology
chemical_list: C076093:vasotocin, (beta-mercapto-beta,beta-cyclopentamethylenepropionic acid)-O-methyl-Tyr(2)-Thr(4)-Orn(8)-Tyr(9)-NH2; D010121:Oxytocin; D014668:Vasotocin