[Sites of androgen overproduction in the polycystic ovary (author's transl)].

T elucidate the possible intraovarian site for androgen overproduction in the polycystic ovary (PCO), we investigated relative contribution of follicular and stromal compartments in steroidogenesis by in vitro experiments. The largest follicle and stoma were dissected from the PCO tissue obtained by wedge resection. A portion of each tissue was taken for histology and slices of each tissue were incubated with acetate-1-14C for 3 hours. Incorporation into progestins, androgens and estrogens was assessed by the reverse isotope dilution technique. Qualitatively, a predominant incorporation into androstenedione (76-88%) with little incorporation into estrogens (0.6-2.5%) was commonly observed in the follicle with marked hyperthecosis found in 3 typical PCOs, whereas a lesser incorporation into androstenedione (51-57%) with a slight increase into estrogens (6.4-14.6%) was verified in the follicles with mild hyperthecosis in 2 atypical PCOs. Quantitatively, actual incorporation into androstenedione was the greatest in the typical PCO follicles, followed by the atypical PCO follicles and the least or almost negligible in the stroma of PCOs. We concluded that atretic follicles rather than the stroma are principal sites of androgen overproduction by PCOs, and the androgenic capacity is related positively to the grade of hyperthecosis.