title: Sexual orientation, proceptivity, and receptivity in the male rat as a function of neonatal hormonal manipulation.
abstract: The influence of neonatal androgen on the potential to exhibit feminine sexual behavior was investigated. Male rats castrated on Day 0 but not those castrated on Day 4 or later showed hop/darting, ear wiggling, and lordotic behavior in response to treatment with estrogen and progesterone in adulthood at a frequency equal to that of females. Neonatal treatment with testosterone propionate (1 mg/rat for 4 days) abolished the capacity to show these behaviors. In subsequent experiments, involving castration of male rats at 0 or 4 hr after cesarean delivery, the effect of the postnatal surge of testicular secretions on the expression of female sexual behavior was investigated. No differences were seen in the frequency of hop/darting, ear wiggling, and receptivity between males castrated immediately or 4 hr after delivery. In a preference test where the experimental male could choose between an estrous female and a sexually active male, the neonatally castrated males preferred the company of a male when treated with estrogen and progesterone. The implantation of testosterone resulted in a preference for an estrous female. It was concluded that testicular secretions in the newborn male influence adult sexual orientation and suppress the ability to show proceptive and receptive behaviors.
authors.affiliation: Department of Psychology, University of Göteborg, Sweden.
authors.forename: J
authors.initials: J
authors.lastname: Vega Matuszczyk
authors.forename: A
authors.initials: A
authors.lastname: Fernandez-Guasti
authors.forename: K
authors.initials: K
authors.lastname: Larsson
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D004958:Estradiol / Q000494:pharmacology*; D008297:Male; D009919:Orchiectomy; D011374:Progesterone / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D012733:Sex Differentiation / Q000187:drug effects*; D012726:Sexual Behavior, Animal / Q000187:drug effects*; D012741:Sexual Maturation / Q000187:drug effects; D013739:Testosterone / Q000494:pharmacology*
chemical_list: D013739:Testosterone; D011374:Progesterone; D004958:Estradiol