title: Sexual differentiation of oxytocin stress responsiveness: effect of neonatal androgenization, castration and a luteinizing hormone-releasing hormone antagonist.
abstract: The plasma OT increment following stress in rats is sexually dimorphic, females exhibiting greater responses than males. We have investigated the role of neonatal androgen secretion in determining the sex-typical level of response. Castration of male pups either surgically or functionally (GnRH antagonist treatment) within either 2 h or 5 days of birth did not elevate the OT responses of adult males. In contrast, androgenization of female pups (testosterone, 1.25 mg/pup) within 5 days of birth markedly reduced the OT stress responses of adults to a level insignificantly different to males. The results show that neonatal androgens can exert organizational effects on OT regulatory mechanisms. Since neonatal castration was ineffective it would appear that a prenatal defeminization or masculinization event determines OT stress responsiveness in males.
authors.affiliation: Medical Unit, Charing Cross & Westminster Medical School, Westminster Hospital, London, UK.
authors.forename: D A
authors.initials: DA
authors.lastname: Carter
authors.forename: E
authors.initials: E
authors.lastname: Saridaki
authors.forename: S L
authors.initials: SL
authors.lastname: Lightman
mesh_terms: D000818:Animals; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives* / Q000494:pharmacology; D008297:Male; D009919:Orchiectomy; D010052:Ovariectomy; D010121:Oxytocin / Q000097:blood*; D011863:Radioimmunoassay; D051381:Rats; D011919:Rats, Inbred Strains; D012727:Sex Characteristics; D013312:Stress, Physiological / Q000097:blood*; D013739:Testosterone / Q000494:pharmacology*; D013997:Time Factors
chemical_list: D007987:Gonadotropin-Releasing Hormone; D013739:Testosterone; D010121:Oxytocin