Progesterone, 17α-hydroxyprogesterone,androgens and oestrogens in bovine ovarian cysts

The concentration of steroid hormones in cystic follicular fluid was determined in cows with cystic ovaries. There was a significant difference in concentrations of the hormones from the cysts with granulosa cell layers, and the cysts without granulosa cell layers or only 2 to 3 layers with pycnotic nuclei in the granulosa cells (P < 0.01). The cystic follicles that consist of both thecal- and granulosa cell layers contained a low amount of progesterone and high levels of 17α-hydroxyprogesterone, androgens and oestrogens, not different from preovulatory follicles.In contrast, cysts that consist only of thecal cell layers contained a very high amount of progesterone, but very low levels of 17α-hydroxyprogesterone, androgens and oestrogens. That is functionally similar to the bovine corpus luteum which produces high concentrations of progesterone but has no or very low 17α-hydroxylase activity.In conclusion, the cystic follicles without granulosa cells are not capable of secreting 17α-hydroxyprogesterone, androgens and oestrogens, in spite of high levels of progesterone. It may be suggested that in these cysts there is a blockade of 17α-hydroxylase activity.