Antagonism of Androgenic and Anti-androgenic Agents in their Action on the Rat Fetus1

Abstract

The antagonism of testosterone propionate and 6-chloro-Δ⁶-l,2α-methylene- 17 α-hydroxyprogesterone acetate (an antiandrogenic agent) on the development of the genitalia of rat fetuses after simultaneous administration of both steroids during pregnancy was examined. The anti-androgenic agent showed a dose-dependent inhibitory effect on the masculinization of female fetuses caused by the administration of testosterone propionate. However, the feminization of male fetuses provoked by the testosterone antagonist is not or is only slightly antagonized by the additional administration of testosterone propionate. (Endocrinology75: 428,1964)