The role of inhibin in women with polycystic ovary syndrome (PCOS).
Human follicular fluids from normal women and from women with polycystic ovary syndrome (PCOS) were collected at various stages of the menstrual cycle, and inhibin and steroid contents were determined by rat anterior pituitary cell monolayer bioassay system and specific RIAs, respectively. Inhibin contents in viable follicles were significantly higher than those in atretic and in cystic follicles. Preovulatory and luteal phase follicles had lower inhibin levels than viable follicles in normal women. A significant inverse correlation was found between inhibin contents and androstenedione to estrogen ratios. The inhibin contents in PCOS follicles were not significantly different from those of viable follicles of normal women at the early follicular phase, but they were significantly higher than in atretic follicles. Since PCOS ovaries often contain more antral follicles than normal ovaries, it could be that this potential source of inhibin may be greater than in normal ovaries. Furthermore, 9 out of 10 follicles in any ovary of normal women are atretic and contribute less inhibin production, whereas PCOS ovaries contain many follicles capable of secreting considerable amounts of inhibin. Therefore, PCOS ovaries totally may secrete more inhibin than normal ovaries. This higher potency of PCOS ovaries to secrete inhibin along with higher serum estrogen levels may be responsible for the disparity between basal LH and FSH levels in PCOS.
Tanabe
K
K
Department of Obstetrics and Gynecology, School of Medicine, Keio University, Japan.
Saijo
A
A
Park
J Y
JY
Kohriyama
S
S
Sano
Y
Y
Nakamura
Y
Y
Iizuka
R
R
D000818:Animals; D001681:Biological Assay; D002478:Cells, Cultured; D004967:Estrogens / Q000378:metabolism; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood / Q000378:metabolism; D015571:Follicular Fluid / Q000378:metabolism; D005498:Follicular Phase; D007987:Gonadotropin-Releasing Hormone; D006801:Humans; D007265:Inhibins / Q000378:metabolism*; D008183:Luteal Phase; D007986:Luteinizing Hormone / Q000097:blood; D006080:Ovarian Follicle / Q000378:metabolism / Q000473:pathology; D010060:Ovulation; D010903:Pituitary Gland, Anterior / Q000187:drug effects / Q000378:metabolism; D011085:Polycystic Ovary Syndrome / Q000378:metabolism* / Q000473:pathology; D011374:Progesterone / Q000378:metabolism; D051381:Rats
D004967:Estrogens; D007987:Gonadotropin-Releasing Hormone; D011374:Progesterone; D007265:Inhibins; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone