INFLUENCE OF NEONATAL GESTAGEN INJECTION ON THE DIFFERENTIATION OF PSYCHOSEXUALITY IN FEMALE RATS

• Published in: Acta endocrinologica (Copenhagen) Vol. 67; no. 3; pp. 544 - 550
• Main Authors: Steinbeck, H, Cupceancu, B, Mehring, M, Neumann, F
• Format: Journal Article
• Language: English
• Published: Denmark 01.07.1971
• Subjects: Androgens - pharmacology; Animals; Estrogens - pharmacology; Female; Hydroxyprogesterones - pharmacology; Medroxyprogesterone - pharmacology; Megestrol - pharmacology; Norethandrolone - pharmacology; Norethindrone - pharmacology; Psychosexual Development - drug effects; Rats; Time Factors
• ISSN: 0804-4643; 0001-5598; 1479-683X
• DOI: 10.1530/acta.0.0670544

ABSTRACT The influence of neonatal injection of gestagens with androgenic, oestrogenic, or no side activities on sexual behaviour differentiation was studied in female rats. Single injections of norethindrone acetate, ethinodiol diacetate and norethindrone oenanthate, which are steroids with inherent oestrogenic activities, suppressed the capacity to display lordosis responses in adult life after hormonal stimulation. Both norethindrone esters also caused a certain shift of psychosexuality towards masculinity. The incidence of bisexuality was, however, extremely low in all the rats. Androgenic gestagens, i. e. d.l-norgestrel and norethandrolone, did not suppress female differentiation of sexuality; there was moreover no increase in male behavioural patterns. Norhydroxyprogesterone caproate, megestrol acetate and a new synthetic progesterone derivative (clomegestone acetate), all steroids with no side activities, were without any effect on mating behaviour differentiation. Allylestrenol and medroxyprogesterone acetate suppressed the capacity to display feminine mating patterns but did not induce male behaviour. It is most likely, however, that this result is due to the administration of higher gestagen doses rather than to any side effects of either steroid.