Steroid hormones in the postovulatory follicle of the domestic fowl (Gallus domesticus).

Progesterone, androstenedione, testosterone, oestrone and oestradiol were measured in the postovulatory follicle (POF) at various times up to 52 h after ovulation. The 3-fold decrease in progesterone, the major constituent, which occurred over the first 15--20 h resembled the changes previously described for the enzyme, 3beta-hydroxy-steroid dehydrogenase. At 1 h before ovulation the granulosa cells of the anteovulatory follicle (AOF) contained 50 times more progesterone than the POF granulosa fraction collected 2--3 h later. The thecal portion of the AOF had progesterone concentrations 5 times those of the POF theca, but the latter contained higher concentrations of androstenedione and oestrone.