Estrogen-induced sexual receptivity and localization of 3H-estradiol in brains of female mice: effects of 5 alpha-reduced androgens, progestins and cyproterone acetate
Luttge, W.G.; Jasper, T.W.; Gray, H.E.; Sheets, C.S.
Pharmacology Biochemistry and Behavior 6(5): 521-528
1977
ISSN/ISBN: 0091-3057 PMID: 896889 DOI: 10.1016/0091-3057(77)90111-3Document Number: 434828
Sexual receptivity induced in ovariectomized CD-1 mice with chronic daily administration of estradiol benzoate (EB; 2 mcg) was investigated and localization of tritiated estradiol in brains of these mice attempted. After 10 days of EB priming dihydrotestosterone (DHT) was given (1 mg/day) and again tested for receptivity. This was followed by further testing after DHT had been stopped. In a 2nd experiment the effect of varying dose and time of administration of DHT on estrogen-induced receptivity was attempted. Dosage of DHT was varied from 500 mcg to 1 mg and time of injection was varied from concurrent with EB injection to 12 hours after. In a 3rd study the effects of DHT, cyproterone acetate (CA), and 3alpha- or 3beta-androstanediol were examined with relation to receptivity. A dosage schedule designed to inhibit receptivity was used. Finally, the effects of DHT and 3alpha- and 3beta-androstanediol on tritiated estradiol localization in brain and pituitary was investigated. Estrogen-induced receptivity was blocked by concurrent administration of the 5aplha-reduced androgen, and DHT. Receptivity was restored in these females with progesterone. However, priming with dihydroprogesterone 6 hours prior to testing was ineffective in restoring receptivity. Delayed DHT injections greatly reduced inhibitory properties. Receptivity was also blocked by concurrent treatment with CA and 3alpha-androstanedio. 3beta-androstanediol was ineffective in blocking receptivity. Pretreatment with DHT or 3alpha- or 3beta-androstanediol failed to affect tritiated estradiol accumulation consistently in crude nuclear and supernatant factions from brain and pituitary.