title: Age and sex differences in oxytocin and vasopressin V1a receptor binding densities in the rat brain: focus on the social decision-making network.
abstract: Oxytocin (OT) and vasopressin (AVP) regulate various social behaviors via activation of the OT receptor (OTR) and the AVP V1a receptor (V1aR) in the brain. Social behavior often differs across development and between the sexes, yet our understanding of age and sex differences in brain OTR and V1aR binding remains incomplete. Here, we provide an extensive analysis of OTR and V1aR binding density throughout the brain in juvenile and adult male and female rats, with a focus on regions within the social decision-making network. OTR and V1aR binding density were higher in juveniles than in adults in regions associated with reward and socio-spatial memory and higher in adults than in juveniles in key regions of the social decision-making network and in cortical regions. We discuss possible implications of these shifts in OTR and V1aR binding density for the age-specific regulation of social behavior. Furthermore, sex differences in OTR and V1aR binding density were less numerous than age differences. The direction of these sex differences was region-specific for OTR but consistently higher in females than in males for V1aR. Finally, almost all sex differences in OTR and V1aR binding density were already present in juveniles and occurred in regions with denser binding in adults compared to juveniles. Possible implications of these sex differences for the sex-specific regulation of behavior, as well potential underlying mechanisms, are discussed. Overall, these findings provide an important framework for testing age- and sex-specific roles of OTR and V1aR in the regulation of social behavior.
authors.affiliation: Neurobiology of Social Behavior Laboratory, Department of Psychology, Boston College, McGuinn 300, 140 Commonwealth Ave, Chestnut Hill, MA, 02467, USA. caroline.smith.3@bc.edu.
authors.forename: Caroline J W
authors.identifier: http://orcid.org/0000-0003-2811-0095
authors.initials: CJW
authors.lastname: Smith
authors.affiliation: Neurobiology of Social Behavior Laboratory, Department of Psychology, Boston College, McGuinn 300, 140 Commonwealth Ave, Chestnut Hill, MA, 02467, USA.
authors.forename: Max L
authors.initials: ML
authors.lastname: Poehlmann
authors.affiliation: Neurobiology of Social Behavior Laboratory, Department of Psychology, Boston College, McGuinn 300, 140 Commonwealth Ave, Chestnut Hill, MA, 02467, USA.
authors.forename: Sara
authors.initials: S
authors.lastname: Li
authors.affiliation: Neurobiology of Social Behavior Laboratory, Department of Psychology, Boston College, McGuinn 300, 140 Commonwealth Ave, Chestnut Hill, MA, 02467, USA.
authors.forename: Aarane M
authors.initials: AM
authors.lastname: Ratnaseelan
authors.affiliation: Neurobiology of Social Behavior Laboratory, Department of Psychology, Boston College, McGuinn 300, 140 Commonwealth Ave, Chestnut Hill, MA, 02467, USA.
authors.forename: Remco
authors.initials: R
authors.lastname: Bredewold
authors.affiliation: Neurobiology of Social Behavior Laboratory, Department of Psychology, Boston College, McGuinn 300, 140 Commonwealth Ave, Chestnut Hill, MA, 02467, USA.
authors.forename: Alexa H
authors.initials: AH
authors.lastname: Veenema
mesh_terms: D000818:Animals; D001345:Autoradiography; D001921:Brain / Q000033:anatomy & histology / Q000378:metabolism*; D003657:Decision Making / Q000502:physiology*; D005260:Female; D008297:Male; D009434:Neural Pathways / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D018045:Receptors, Oxytocin / Q000378:metabolism*; D017483:Receptors, Vasopressin / Q000378:metabolism*; D012727:Sex Characteristics; D012919:Social Behavior; D065852:Spatial Memory / Q000502:physiology
chemical_list: D018045:Receptors, Oxytocin; D017483:Receptors, Vasopressin; C588222:oxytocin receptor, rat
keywords: Development; Juvenile; Oxytocin; Oxytocin receptor; Sex differences; V1a receptor; Vasopressin