Effects of androstenedione and progesterone on oestrous swelling of the ferret vulva.

Abstract

Quantitative data are given of the anti-oestrogenic action of progesterone on the vulva of the normal oestrous ferret, and the oöphorectomized animal treated with oestrogen implants. Initial experiments that suggested a similar action of androstenedione, such as has been reported on the mouse vagina, were not confirmed. Amounts of androstenedione at least 80 times as great as those of progesterone that were effective in collapsing the normal oestrous vulva, and at least 10 times as great as those that antagonized the effect of oestrogen on the vulva and vaginal smear of the castrate, produced no effect. In view of the different method of administration, among other factors, exact equality of relative anti-oestrogenic potency in mouse and ferret was not to be expected; but the observed difference suggests that androstenedione may be metabolized differently in the two species, the metabolites varying in anti-oestrogenic action.