title: Effects of intranasal and peripheral oxytocin or gastrin-releasing peptide administration on social interaction and corticosterone levels in rats.
abstract: The intranasal route of drug administration has gained increased popularity as it is thought to allow large molecules, such as peptide hormones, more direct access to the brain, while limiting systemic exposure. Several studies have investigated the effects of intranasal oxytocin administration in humans as this peptide is associated with prosocial behavior. There are, however, few preclinical studies investigating the effects of intranasal oxytocin administration in rodents. Oxytocin modulates hypothalamic-pituitary-adrenal (HPA) axis functioning and it has been suggested that oxytocin's ability to increase sociability may occur through a reduction in stress reactivity. Another peptide that appears to influence both social behavior and HPA axis activity is gastrin-releasing peptide (GRP), but it is not known if these GRP-induced effects are related. With this in mind, in the present study, we assessed the effects of intranasal and intraperitoneal oxytocin and GRP administration on social interaction and release of corticosterone in rats. Intranasal and intraperitoneal administration of 20, but not 5 μg, of oxytocin significantly increased social interaction, whereas intranasal and peripheral administration of GRP (20 but not 5 μg) significantly decreased levels of social interaction. In addition, while intranasal oxytocin (20 μg) had no effect on blood corticosterone levels, a marked increase in blood corticosterone levels was observed following intraperitoneal oxytocin administration. With GRP, intranasal (20 μg) but not peripheral administration increased corticosterone levels. These findings provide further evidence that intranasal peptide delivery can induce behavioral alterations in rodents which is consistent with findings from human studies. In addition, the peptide-induced changes in social interaction were not linked to fluctuations in corticosterone levels.
authors.affiliation: University of Ottawa Institute of Mental Health Research, 1145 Carling Avenue, Ottawa, ON K1Z 7K4, Canada; Department of Psychology, University of Ottawa, Ottawa, ON K1N 6N5, Canada.
authors.forename: Pamela
authors.initials: P
authors.lastname: Kent
authors.affiliation: University of Ottawa Institute of Mental Health Research, 1145 Carling Avenue, Ottawa, ON K1Z 7K4, Canada; Department of Psychology, University of Ottawa, Ottawa, ON K1N 6N5, Canada.
authors.forename: Alisha
authors.initials: A
authors.lastname: Awadia
authors.affiliation: University of Ottawa Institute of Mental Health Research, 1145 Carling Avenue, Ottawa, ON K1Z 7K4, Canada.
authors.forename: Leah
authors.initials: L
authors.lastname: Zhao
authors.affiliation: University of Ottawa Institute of Mental Health Research, 1145 Carling Avenue, Ottawa, ON K1Z 7K4, Canada; Department of Psychology, University of Ottawa, Ottawa, ON K1N 6N5, Canada.
authors.forename: Donna
authors.initials: D
authors.lastname: Ensan
authors.affiliation: University of Ottawa Institute of Mental Health Research, 1145 Carling Avenue, Ottawa, ON K1Z 7K4, Canada; Department of Psychology, University of Ottawa, Ottawa, ON K1N 6N5, Canada.
authors.forename: Dinuka
authors.initials: D
authors.lastname: Silva
authors.affiliation: University of Ottawa Institute of Mental Health Research, 1145 Carling Avenue, Ottawa, ON K1Z 7K4, Canada; Department of Psychology, University of Ottawa, Ottawa, ON K1N 6N5, Canada.
authors.forename: Christian
authors.initials: C
authors.lastname: Cayer
authors.affiliation: University of Ottawa Institute of Mental Health Research, 1145 Carling Avenue, Ottawa, ON K1Z 7K4, Canada; Department of Psychology, University of Ottawa, Ottawa, ON K1N 6N5, Canada.
authors.forename: Jonathan S
authors.initials: JS
authors.lastname: James
authors.affiliation: Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1N 6N5, Canada.
authors.forename: Hymie
authors.initials: H
authors.lastname: Anisman
authors.affiliation: University of Ottawa Institute of Mental Health Research, 1145 Carling Avenue, Ottawa, ON K1Z 7K4, Canada; Department of Psychology, University of Ottawa, Ottawa, ON K1N 6N5, Canada; Department of Psychiatry, University of Ottawa, Ottawa, ON K1N 6N5, Canada; Institute of Neuroscience, Carleton University, Ottawa, ON K1S 5B6, Canada. Electronic address: merali@uottawa.ca.
authors.forename: Zul
authors.initials: Z
authors.lastname: Merali
mesh_terms: D000281:Administration, Intranasal; D000818:Animals; D003345:Corticosterone / Q000097:blood*; D004305:Dose-Response Relationship, Drug; D019886:Gastrin-Releasing Peptide / Q000008:administration & dosage* / Q000494:pharmacology*; D007274:Injections, Intraperitoneal; D008297:Male; D010121:Oxytocin / Q000008:administration & dosage* / Q000494:pharmacology*; D051381:Rats; D012919:Social Behavior
chemical_list: D010121:Oxytocin; D019886:Gastrin-Releasing Peptide; D003345:Corticosterone
keywords: Corticosterone; Gastrin-releasing peptide; Hypothalamic-pituitary-adrenal axis; Intranasal administration; Oxytocin; Social interaction