A Comparative Study of the Conversion of Testosterone to 17β-Hydroxy-5α-androstan-3-one (Dihydrotestosterone) by Prostate and Epididymis

Abstract

The conversion of testosterone-1,2-³H to dihydrotestosterone-³H has been measured under standardized conditions in slices of various tissues from 11 species. In the rat, the highest rates of this conversion were observed in prostate, epididymis, seminal vesicle, penis, preputial gland and scrotum, the other tissues exhibiting much lower values. When the rate of dihydrotestosterone formation was compared in prostate from 9 species, the values observed varied from 569±69 μμmoles/100 mg tissue in the rat to immeasurably low levels in the bull (4±3 μμmoles/100 mg/hr), whereas this conversion was demonstrable in all epididymal tissues studied. Furthermore, dihydrotestosterone formation was measurable in all of the immature prostates studied, including that from calf, and in a variety of other tissues known to be under androgenic control—duck preen gland, the comb and wattle of the chicken, and the preputial gland of rat and mouse. Dihydrotestosterone formation was not demonstrated in any muscle tested. It has been concluded from these findings that the formation of dihydrotestosterone is not an obligatory reaction for all of the effects of androgen; it is possible, however, that dihydrotestosterone may mediate the cell proliferative effects of testosterone in the prostate.