Luteinizing hormone receptors in ovarian follicles of patients with polycystic ovarian disease.

Abstract

Wedge resection was performed in 12 patients with polycystic ovarian disease, and cell samples from the cystic follicles were assayed for LH(hCG) receptor using [125I]iodo-hCG as a ligand hormone. Simultaneously to wedge resection, blood samples were taken for serum FSH, LH, 17 beta-estradiol, progesterone, and testosterone RIA measurements. Serum LH was regularly elevated (16.0-57.1 U/liter), whereas FSH (5.2-11.5 U/liter) was within the normal reference range. The LH to FSH ratio was between 2.1-7.8. The 17 beta-estradiol concentrations (0.12-0.23 nmol/liter) were within the normal reference range found during the early follicular phase. Only 3 patients had progesterone levels exceeding the assay sensitivity limit of 0.1 nmol/liter. Ony 3 of the 11 patients assayed for serum testosterone had values exceeding the upper limit of the reference range. Seventy-seven percent of the ovarian follicular samples showed specific binding of [125I]iodo-hCG. The number of receptors in positive samples averaged 0.67 +/- 0.11 fmol/mg homogenate protein, which is clearly lower than that in normal preovulatory follicles. Scatchard analyses revealed a single class of binding sites, with a mean equilibrium association constant of 5.4 X 10(9) M-1 at 37 C. These results suggest that the derangement of follicular development in patients with polycystic ovarian disease probably is not due to the lack of appearance of the LH(hCG) receptor. It is possible that the tonic elevation of serum LH results in a decrease in the number of available receptor sites; this would be one step in the process leading to ovarian changes characteristic of this disease.