Critical Exposure Time for Androgenization of the Rat Hypothalamus Determined by Antiandrogen Injection

Abstract

Summary The simultaneous injection of 0.6 mg cyproterone acetate (CA), an antiandrogen, protects the 5-day-old female rat against the hypothalamic masculinizing action of 30 μg testosterone propionate. When CA was administered 6 or more hours after androgen injection, however, its effectiveness was markedly reduced. It is concluded that a CA-labile component of the process of hypothalamic masculinization, which lasts for less than 6 hours, may consist of the uptake of androgen by hypothalamic neurons.