title: Inhibin B plasma concentrations in oligozoospermic subjects before and after therapy with follicle stimulating hormone.
abstract: The aim of this study was to investigate inhibin B and follicle stimulating hormone (FSH) secretion in a large group of oligozoospermic subjects affected by different degrees of testicular damage, before and after FSH treatment. A total of 135 oligozoospermic subjects (sperm count < 20 x 10(6)/ml) were evaluated for seminal parameters and FSH, luteinizing hormone (LH), testosterone and inhibin B plasma concentrations. Testicular structure was analysed with bilateral fine needle aspiration cytology. Inhibin B showed an inverse correlation with FSH, no correlation with sperm concentration and a significant relationship with intratesticular spermatid number, demonstrating that testicular spermatids play an important role in the control of inhibin B production. Twenty-five subjects with sperm counts < 10 x 10(6)/ml were treated with FSH; 11 of these had basal FSH and inhibin B plasma concentrations in the normal range (group A), while in seven subjects FSH was elevated (> 7 IU/l) with normal inhibin B (group B), and in seven patients FSH was high and inhibin B reduced (< 80 pg/ml) (group C). During treatment, in group A patients inhibin B plasma concentrations increased significantly after 2, 3 and 4 weeks of FSH administration and declined thereafter to pre-treatment concentrations. Groups B and C did not show any modification during the treatment. In the same period, in group A FSH increased significantly after 2, 3 and 4 weeks and subsequently declined. In groups B and C, FSH increased significantly after 2 weeks and remained elevated during the following period. The results of the present study confirm the significant inverse correlation between inhibin B and FSH plasma concentrations in subjects with disturbed spermatogenesis, and demonstrate that inhibin B reflects Sertoli cell function and their interaction with spermatids. FSH and inhibin B concentrations are an expression of the spermatogenic status of seminiferous tubules. FSH treatment seems to modify inhibin B plasma concentrations only in subjects with normal basal FSH and inhibin B, independently from the effects of this therapy on sperm production.
authors.affiliation: Clinica Medica 3, University of Padova, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Foresta
authors.forename: A
authors.initials: A
authors.lastname: Bettella
authors.forename: M
authors.initials: M
authors.lastname: Rossato
authors.forename: G
authors.initials: G
authors.lastname: La Sala
authors.forename: M
authors.initials: M
authors.lastname: De Paoli
authors.forename: M
authors.initials: M
authors.lastname: Plebani
mesh_terms: D000328:Adult; D005640:Follicle Stimulating Hormone / Q000097:blood / Q000627:therapeutic use*; D006801:Humans; D007265:Inhibins / Q000097:blood*; D008297:Male; D009845:Oligospermia / Q000097:blood* / Q000188:drug therapy*; D013076:Sperm Count
chemical_list: D007265:Inhibins; D005640:Follicle Stimulating Hormone