title: Follicular arrest in polycystic ovary syndrome is associated with deficient inhibin A and B biosynthesis.
abstract: BACKGROUND
  Previous studies suggest that inhibin subunit expression is decreased in granulosa cells of women with polycystic ovary syndrome (PCOS).
  
  
  OBJECTIVE
  The objective of this study was to test the hypothesis that inhibin A and inhibin B protein concentrations are also decreased in PCOS follicles.
  
  
  METHODS
  The design was a parallel study.
  
  
  METHODS
  The study was performed at an in vitro fertilization suite.
  
  
  METHODS
  We studied women with regular cycles (n = 36) and women with PCOS (n = 8).
  
  
  METHODS
  Follicular fluid was aspirated from the follicles of women with PCOS (n = 14 follicles) and from women with regular cycles at various times during the follicular phase (n = 50 follicles).
  
  
  METHODS
  Inhibin A and B concentrations from PCOS follicles were compared with those in size-matched follicles, dominant follicles (> or = 10 mm), and subordinate follicles from regularly cycling women.
  
  
  RESULTS
  Inhibin A (220 +/- 38 vs. 400 +/- 72 IU/ml; P < 0.05) and inhibin B (75.4 +/- 10.4 vs. 139 +/- 26 ng/ml; P < 0.05) concentrations were lower in the follicular fluid of PCOS follicles compared with those of size-matched follicles from regularly cycling women. Inhibin A was also lower in the follicular fluid of PCOS compared with subordinate follicles from normal women (577 +/- 166 IU/ml; P < 0.05). Inhibin A concentrations increased with increasing follicle size, resulting in significantly higher follicular fluid concentrations in dominant follicles from normal women compared with PCOS follicles (2298 +/- 228 IU/ml; P < 0.05).
  
  
  CONCLUSIONS
  These data demonstrate that inhibin A and inhibin B concentrations are significantly reduced in the follicular fluid of women with PCOS compared with those in the follicular fluid of size-matched follicles from normal women, consistent with the decreased inhibin subunit mRNA expression in previous studies. These findings point to the potential importance of inhibins in normal follicle development and suggest that inhibin deficiency may play a role in the follicle arrest associated with PCOS.
authors: Reproductive Endocrine Unit, Department of Medicine, Massachusetts General Hospital, 55 Fruit Street, Boston, Massachusetts 02114, USA. cwelt@partners.org
authors: Corrine K
authors: CK
authors: Welt
authors: Ann E
authors: AE
authors: Taylor
authors: Janis
authors: J
authors: Fox
authors: Geralyn M
authors: GM
authors: Messerlian
authors: Judith M
authors: JM
authors: Adams
authors: Alan L
authors: AL
authors: Schneyer
mesh_terms: D028341:Activins / Q000378:metabolism; D000293:Adolescent; D000328:Adult; D000735:Androstenedione / Q000097:blood; D015992:Body Mass Index; D004958:Estradiol / Q000097:blood / Q000378:metabolism; D005260:Female; D043373:Follicle Stimulating Hormone, Human / Q000097:blood; D015571:Follicular Fluid / Q000378:metabolism; D006801:Humans; D028322:Inhibin-beta Subunits / Q000378:metabolism; D007265:Inhibins / Q000097:blood / Q000172:deficiency*; D007986:Luteinizing Hormone / Q000097:blood; D006080:Ovarian Follicle / Q000502:physiology*; D011085:Polycystic Ovary Syndrome / Q000473:pathology*; D013739:Testosterone / Q000097:blood
chemical_list: D043373:Follicle Stimulating Hormone, Human; C422405:activin A; C422362:inhibin A; C422364:inhibin B; D028341:Activins; D013739:Testosterone; D000735:Androstenedione; D004958:Estradiol; D007265:Inhibins; D007986:Luteinizing Hormone; D028322:Inhibin-beta Subunits