Significance of atretic follicles as the site of androgen production in polycystic ovaries.

To examine androgenic potential of polycystic ovaries (PCO), slices of follicular and stromal tissues from the same ovary obtained by wedge resection from two markedly, two moderately and one slightly enlarged PCO were incubated separately with [1-14C] acetate. Incorporation into progestins, androgens and estrogens was assessed by reverse dilution technique with recrystallization to constant specific activity. Although the greatest incorporation into androstenedione with much lesser incorporation into testosterone and dehydroepiandrosterone was observed with all the five follicles, the amount of incorporation into the three steroids increased gradedly with histologically defined magnitude of thecal cell hyperplasia in atretic follicles. Only the stromal tissues from two markedly enlarged PCO produced androgens with a similar pattern of 14C distribution among the steroids, thereby incorporation into the three androgens remaining 5.5% or less of that by the follicles from the same ovary. Preoperative levels of plasma androstenedione and urinary 17-ketosteroids were shown to increase in four patients with PCO containing atretic follicles with thecal cell hyperplasia, but not in one patient with slightly enlarged PCO containing atretic follicles without thecal cell hyperplasia. It is inferred that atretic follicles with thecal cell hyperplasia is a significant source of androgen overproduction by PCO.