OESTROGEN SYNTHESIS IN VITRO BY OVARIES FROM RATS IN DIFFERENT PHASES OF THE OESTROUS CYCLE

Abstract

SUMMARY Ovaries taken from rats in oestrus converted more [4-14C]testosterone to [14C]oestrone and [14C]oestradiol-17β than did ovaries taken at dioestrus. Little difference was found in the conversion of [4-14C]androst-4-ene-3,17-dione to [14C]oestrone by either type of tissue. These results suggest that testosterone, rather than androstenedione, is an endogenous oestrogen precursor in the rat. The ability of the rat ovary to produce oestrogen in vitro from C-19 steroids during dioestrus is discussed.