Hormone Research in Paediatrics
Sex Differentiation and Ovarian Function
Physiological Role of Insulin-Like-Growth-Factor-Binding Protein-4 in Human FolliculogenesisIwashita M.a · Kudo Y.b · Yoshimura Y.c · Adachi T.b · Katayama E.d · Takeda Y.baMaternal and Perinatal Center, and bDepartment of Obstetrics and Gynecology, Tokyo Women’s Medical College, cDepartment of Obstetrics and Gynecology, Keio University, School of Medicine, and dDepartment of Obstetrics and Gynecology, Ogikubo Hospital, Tokyo, Japan
|
|
Log in to MyKarger to check if you already have access to this content.
KAB
Buy a Karger Article Bundle (KAB) and profit from a discount!
If you would like to redeem your KAB credit, please log in.
Save over 20% compared to the individual article price.
Article / Publication Details
Published online: December 09, 2008
Issue release date: 1996
Number of Print Pages: 6
Number of Figures: 0
Number of Tables: 0
ISSN: 1663-2818 (Print)
eISSN: 1663-2826 (Online)
For additional information: https://www.karger.com/HRP
Abstract
Insulin-like growth factor (IGF)-I and IGF-II, and their binding proteins (IGFBPs) have been demonstrated to play important roles in follicular development as intraovarian regulators. Previous studies have demonstrated that the follicular fluid of atretic follicles contains high levels of IGFBP-2 and IGFBP-4, which are known to inhibit the action of IGFs. In this study, we identified IGFBP-4 protease activity in the follicular fluid of developing but not atretic follicles. To elucidate the regulation mechanism of IGFBP-4 proteolytic activity in the ovary, cultured luteinized granulosa cells (GCs) were incubated with various hormones, and proteolyzed IGFBP-4 in the medium was analyzed. IGFBP-4 proteolytic activity was increased when GCs were incubated with IGFs, estradiol or follicle-stimulating hormone (FSH) but not with testosterone. We also showed that IGFBP-4 inhibited IGF-I-induced estradiol release by GCs while proteolyzed IGFBP-4 did not. These results suggest that human luteinized GCs produce IGFBP-4 protease, and that FSH and IGFs may stimulate folliculogenesis by modulating IGFBP-4 degradation in the ovary.
© 1997 S. Karger AG, Basel
Related Articles:
Article / Publication Details
Published online: December 09, 2008
Issue release date: 1996
Number of Print Pages: 6
Number of Figures: 0
Number of Tables: 0
ISSN: 1663-2818 (Print)
eISSN: 1663-2826 (Online)
For additional information: https://www.karger.com/HRP
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
