COMPARATIVE ANTIOESTROGENIC POTENCIES OF PROGESTERONE AND ESTERIFIED 17α-Hydroxy-Progesterone IN THE GUINEA-PIG

Abstract

Five different antioestrogenic activities inherent in progestational compounds such as the antifibromatogenic, antihysterotrophic and antiluteinizing actions, the prevention of the oestrogen\x=req-\ induced opening of the vaginal membrane, and the counteracting of alopecia, have been investigated in the guinea-pig in experiments with 17\g=a\-hydroxyprogesterone and its caproate and acetate.These antioestrogenic properties are either not inherent in the above-mentioned compounds, or only inherent to a slight degree. The very slight antioestrogenic potency of 17 \g=a\-hydroxyprogesterone is not increased by esterification with either caproic or acetic acid.The clinical significance of these findings is discussed.