title: Region-specific associations between sex, social status, and oxytocin receptor density in the brains of eusocial rodents.
abstract: Naturally occurring variations in neuropeptide receptor distributions in the brain contribute to numerous mammalian social behaviors. In naked mole-rats, which live in large social groups and exhibit remarkable reproductive skew, colony-related social behaviors vary with reproductive status. Here we examined whether variation in social status is associated with variations in the location and/or density of oxytocin binding in this species. Autoradiography was performed to assess forebrain oxytocin receptor (OTR) densities in breeding and non-breeding naked mole-rats of both sexes. Overall, males exhibited higher OTR binding in the medial amygdala in comparison to females. While there were no main effects of reproductive status in any region, a sex difference in OTR binding in the nucleus accumbens was mediated by status. Specifically, breeding males tended to have more OTR binding than breeding females in the nucleus accumbens, while no sex difference was observed in subordinates. These effects suggest that oxytocin may act in a sex- and region-specific way that corresponds to reproductive status and associated social behaviors.
authors.affiliation: Department of Psychology, University of Toronto Mississauga, Mississauga, Ontario L5L 1C6, Canada.
authors.forename: S J
authors.initials: SJ
authors.lastname: Mooney
authors.affiliation: Reproductive Neurobiology, Division of Women's Health, School of Medicine, King's College London, London, UK.
authors.forename: C W
authors.initials: CW
authors.lastname: Coen
authors.affiliation: Department of Psychology, University of Toronto Mississauga, Mississauga, Ontario L5L 1C6, Canada; Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario M5S 3G5, Canada; Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario M5S 3G5, Canada. Electronic address: melissa.holmes@utoronto.ca.
authors.forename: M M
authors.initials: MM
authors.lastname: Holmes
authors.affiliation: Department of Psychology, Department of Biology, Program in Neuroscience, Smith College, Northampton, MA 01063, United States. Electronic address: abeery@smith.edu.
authors.forename: A K
authors.initials: AK
authors.lastname: Beery
mesh_terms: D000220:Adaptation, Biological; D000818:Animals; D001345:Autoradiography; D001921:Brain / Q000033:anatomy & histology / Q000187:drug effects / Q000378:metabolism*; D005260:Female; D007398:Interpersonal Relations; D007456:Iodine Isotopes / Q000493:pharmacokinetics; D008297:Male; D019577:Mole Rats; D010121:Oxytocin / Q000031:analogs & derivatives / Q000378:metabolism / Q000493:pharmacokinetics / Q000494:pharmacology; D018045:Receptors, Oxytocin / Q000378:metabolism*; D012727:Sex Characteristics; D012930:Social Dominance; D012931:Social Environment; D014662:Vasoconstrictor Agents / Q000493:pharmacokinetics / Q000494:pharmacology; D014668:Vasotocin / Q000493:pharmacokinetics / Q000494:pharmacology
chemical_list: D007456:Iodine Isotopes; C055830:KB 5-21; D018045:Receptors, Oxytocin; D014662:Vasoconstrictor Agents; D010121:Oxytocin; D014668:Vasotocin
keywords: amygdala; naked mole-rat; nucleus accumbens; oxytocin; receptor autoradiography; social behavior