Skip Navigation

This Article
Right arrow Full Text Freely available
Right arrow FREE Full Text (PDF ) Freely available
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Galeraud-Denis, I.
Right arrow Articles by Carreau, S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Galeraud-Denis, I.
Right arrow Articles by Carreau, S.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

Human Reproduction, Vol. 14, No. 2, 312-317, February 1999
© 1999 European Society of Human Reproduction and Embryology

Inhibitory effect of plasma obtained from hypophysectomized and control women on the assay of bioactive luteinizing hormone

I. Galeraud-Denis1, P. Bouchard2, M. Herlicoviez1, E. Marie1 and S. Carreau3,4

1 Departments of Gynecologie–Obstétrique, CHU Clémenceau, Caen, 2 Endocrinologie, CHU Saint-Antoine, Paris and 3 Biochimie–IRBA, Université de Caen, 14032 Caen Cédex, France

The purpose of this study was to determine the effect of components of female plasma on the value of bioactive luteinizing hormone (LH), especially in the presence of low immunological LH value. Using both an immunoradiometric assay (IRMA) and rat Leydig cell bioassay, immunoreactive (I) and bioactive (B) LH were assessed in plasma collected from women during a gonadotrophin releasing hormone (GnRH) test performed on day 7 of a spontaneous cycle. Two modes of response to an acute administration of GnRH were defined: normal production of gonadotrophins (group I) and excessive secretion (group II) associated with a significant difference in the B/I–LH ratio between the two groups. The B/I–LH ratio did not vary with sampling time during the test in either group. The addition of LH-free plasma collected from hypophysectomized women caused a 30% decrease in testosterone production compared to control values (in the presence or absence of hLH standard). A partial restoration of testosterone production was observed if plasma was first treated with PEG 12%. The inhibitory factor(s) was also present in plasma from ovulatory women, even after treatment by an antibody against the entire LH molecule. The effect of normal (A) or low I-LH plasma (B) on testosterone production varied strongly according to the plasma volume added to the bioassay, as well as to plasma treatments. Diethylether treatment caused a 50% decrease in testosterone secretion for plasma B (but not for A) whereas a diminution of the steroidogenesis is observed after a PEG treatment of plasma A (but not for B), suggesting that different inhibitory factors are present in plasmas A and B. Therefore the LH bioactivity measured in the rat Leydig cell assay, in terms of testosterone output, seems to represent a balance between the LH molecule and the presence of inhibitory factors in the plasma.

Key words: hypophysectomy/inhibitory factors/LH bioactivity/plasma

4 To whom correspondence should be addressed


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.