+1 Recommend
1 collections
      • Record: found
      • Abstract: found
      • Article: found

      Prolactin-Releasing Action of a Low Dose of Exogenous Gonadotropin-Releasing Hormone Throughout the Human Menstrual Cycle

      Read this article at

          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.


          Pharmacological doses of gonadotropin-releasing hormone (GnRH) are known to induce prolactin (PRL) release in different pathological states. The same effect can be observed in postmenopausal women and during the phases of menstrual cycle characterized by high estrogen levels. With the aim to evaluate whether nonpharmacological doses of GnRH are also able to induce PRL release, gonadotropin and PRL response to a low dose of GnRH (10 µg, i.v. bolus) was evaluated in 70 normal women during different phases of their menstrual cycle. A significant PRL increase was observed in 33% of subjects during the first days of the cycle (menstrual phase; days 1–3 from the beginning of menstrual bleeding; n = 6), in 24% of subjects during early follicular phase (days – 10 to -8 from LH peak; n= 17); in 38% of subjects during midfollicular phase (days – 6 to – 4 from LH peak; n = 8); in 78% of subjects during preovulatory phase (days – 2 to – 1 from LH peak; n = 9); in 67% of subjects during postovulatory phase (days + 1 to +2 from LH peak; n = 6) and in 42% of subjects during midluteal phase (days +5 to +8 from LH peak; n = 24). In brief, the increase of mean PRL levels after GnRH administration was only significant (p < 0.05) during pre- and postovulatory phases. The percentage of patients who showed a PRL response during the different phases of menstrual cycle was significantly correlated to the mean maximal net increase of LH (r = 0.927; p < 0.01) and to the mean maximal net increase of FSH (r = 0.926; p < 0.01). In conclusion, the present data show that in normal cycling women the administration of exogenous GnRH induces PRL release even at low doses. The PRL-releasing effect of GnRH is variable throughout the menstrual cycle and it is maximal during the periovulatory period. The significant correlation between PRL release and gonadotrophs responsiveness to GnRH suggests that a paracrine interaction between gonadotrophs and lactotrophs might exist also in humans.

          Related collections

          Author and article information

          S. Karger AG
          01 April 2008
          : 44
          : 3
          : 326-330
          Department of Obstetrics Gynecology, School of Medicine, University of Pisa, Italy
          124664 Neuroendocrinology 1986;44:326–330
          © 1986 S. Karger AG, Basel

          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.

          Page count
          Pages: 5
          Original Paper


          Comment on this article