EFFECT OF STEROID HORMONES ON OESTROGEN-INDUCED UTERINE GLYCOGEN SYNTHESIS

Abstract

SUMMARY Uterine weight, water, glycogen and glucose responses were analysed for 96 hr. after a single dose or daily doses of oestradiol given to ovariectomized adult rats. Six hr. after a single dose of oestradiol the uterine glycogen concentration doubled, reached a maximum of 4 times the control value at 12 hr. and then declined during the 16–48 hr. period. The ability of cortisol, deoxycorticosterone, progesterone, 17-ethyl-19-nortestosterone (Nilevar) or testosterone propionate to inhibit these responses was determined at 6 hr. (the initial period of maximum oestrogen action) and at 24 hr. (period of uterine glycogenolysis). A single injection of the antagonist given at the same time as oestrogen had no effect on the 6 hr. glycogen response. Pretreatment with cortisol, progesterone or testosterone propionate for 3 days caused a 30–50% inhibition of the oestrogen-induced increase. Multiple doses of testosterone propionate by itself were glycogenic. Single doses of the compounds appeared to be more effective at 24 hr. Multiple doses of cortisol, deoxycorticosterone, progesterone and testosterone propionate inhibited the 24 hr. glycogen response to oestradiol by 30–50%.