The effects of Δ4-androstenedione and Δ5-androstenediol on castrated and ovariectomized rats

Abstract

Expts. were performed on 7 normal and 59 castrated [male] rats, and on 9 normal [female] and 62 ovariectomized rats, belonging to 27 litters, for the purpose of investigating the action of [DELTA] 4-adrostenedione and [DELTA]5-androstenediol. Both these artificial sexual hormones undoubtedly have both [male] and [female] sexual activities, the weight, size and histological structures of the organs atrophied after gonadectomy being restored towards but not to the normal condition. The weight and size of both the [male] and [female] preputial glands, however, become normal or supranormal after the injections. The hyper-trophying effect on the [female] preputial glands places both these hormones biologically (the author''s definition) in the group of [male] hormones (e.g., testosterone) and not in that of [female] hormones (e.g., oestrone). In the doses used, androstenedione shows a co-operative activity with oestrone on the [female] sexual organs only, but not on the [male] organs; androstenediol shows no co-operative activity with oestrone either on the [male] or [female] organs. On the contrary there is histological evidence of an antagonistic effect of oestrone on the action of androstenediol on some of the [female] sexual organs. There is cooperative activity on the [male] sexual organs between androstenedione and testosterone, especially on the seminal vesicles. In [female] rats the thickened peripheral end of the urethra atrophies considerably after ovariec-tomy, but after the injection of androstenedione into spayed rats it hypertrophies into a structure which is much larger than that seen in normal rats, and is reminiscent of a clitoris or rudimentary penis. Oestrone does not have this effect. Both hormones cause a definite decrease in the weight of the adrenals and an increase in the rate of involution of the thymus in both castrated and ovariectomized rats (except that in [male][male] the effect of androstenediol on the thymus was indefinite). The addition of oestrone seems to depress this action on the adrenals, especially in the case of androstenediol. The effects of these hormones on the other organs, on the fat deposition and on the gain in body weight are also discussed.