Further studies on a nonsteroidal anti-androgen.

Abstract

Ro 5-2537 [2-(l-ethinyl-l-hydroxyethyl)-7-oxo-l,2,3,4,4o-,4j8,5,6,7,9,10,10adodecahydrophenanthrene] antagonized the androgenicity of androstenedione, nortestosterone and fluoxymesterone in the castrated rat. The preparation was also effective in blocking the androgenic responses to testosterone enanthate and testosterone propionate as measured by chick comb responses. Ro 5-2537 was not androgenic either in the castrated rat or in the chick. Ro 5-2537 failed to inhibit the uterotrophic activity of testoster one and did not antagonize seminal vesicle stimulation by estradiol. Ro 5-2537 manifested uterotrophic activity when administered to immature female rats and inhibited the uterine weight increase produced by concurrent stilbestrol administration. Ro 5-2537 failed to inhibit unilateral ovarian compensatory hypertrophy. (Endocrinology78: 549, 1966)