title: Growing up in the family or growing up alone influences behavior and hormones, but not arginine vasopressin receptor 1a expression in male African striped mice.
abstract: In many species males display alternative reproductive tactics (ARTs). While males of different tactics differ behaviorally in the field, it is often not known whether these behavioral differences would also occur under standardized laboratory conditions, nor how ARTs are regulated by the brain. In the present study we kept male African striped mice (Rhabdomys pumilio) in captivity either in family groups or solitary, to mimic ARTs observed in the field. This allowed us to study these males behaviorally under standardized conditions, to replicate physiological findings from the field, and to study the expression of the arginine vasopressin 1a receptor (AVPR1a) in their brains. Changes in either peptide release or receptor expression (or both) might regulate ARTs with differential timelines, with peptide secretion being faster than receptor expression. As observed in the field, family living males had higher corticosterone but lower testosterone levels than singly housed males. Surprisingly, singly housed males were less aggressive while at the same time having higher testosterone levels. We found no differences in AVPR1a expression. In a previous study it was shown that singly housed males have higher levels of AVP stored in their brain, which potentially could be secreted when the social situation changes, for example to establish social bonds. Our study on AVPR1a suggests the hypothesis that, given that the receptor distribution and expression of singly housed males do not differ from that of family-living males, the brains of singly-housed males have a similar capacity to be responsive to AVP when given the chance to interact socially.
authors.affiliation: Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland; School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Johannesburg, South Africa; Université de Strasbourg, IPHC-DEPE, 23 rue Becquerel, 67087 Strasbourg, France; CNRS, UMR7178, 67087 Strasbourg, France. Electronic address: carsten.schradin@iphc.cnrs.fr.
authors.forename: Carsten
authors.initials: C
authors.lastname: Schradin
authors.affiliation: Department of Psychology, University of California, Davis, CA 95616, USA.
authors.forename: Rebecca H
authors.initials: RH
authors.lastname: Larke
authors.affiliation: Department of Psychology, University of California, Davis, CA 95616, USA.
authors.forename: Karen L
authors.initials: KL
authors.lastname: Bales
mesh_terms: D000374:Aggression; D000818:Animals; D001127:Arginine Vasopressin / Q000378:metabolism; D001345:Autoradiography; D001921:Brain / Q000254:growth & development / Q000378:metabolism*; D003345:Corticosterone / Q000097:blood; D006799:Housing, Animal; D008297:Male; D008426:Maternal Deprivation; D051189:Murinae / Q000254:growth & development* / Q000378:metabolism*; D010333:Paternal Deprivation; D017483:Receptors, Vasopressin / Q000378:metabolism*; D012919:Social Behavior; D012934:Social Isolation; D013739:Testosterone / Q000097:blood
chemical_list: D017483:Receptors, Vasopressin; D001127:Arginine Vasopressin; D013739:Testosterone; D003345:Corticosterone
keywords: Communal breeding; Helper; Intra-specific variation; Paternal care; Prairie vole; Social flexibility; Social organization