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

      The Actions of Prostaglandin E 2, Naloxone and Testosterone on Starvation-Induced Suppression of Luteinizing Hormone-Releasing Hormone and Luteinizing-Hormone Secretion

      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.


          In man and other mammals, starvation is accompanied by a severe suppression of luteinizing hormone-releasing hormone (LHRH) and luteinizing-hormone (LH) secretion, which is caused by unknown alterations in hypothalamic functions. Prostaglandin E<sub>2</sub> (PGE<sub>2</sub>), endorphins and testosterone (T) are know to be strongly involved in the regulation of LHRH release. The present study examined whether the influence of these substances on LHRH and LH secretion was affected by starvation. In vitro experiments checked the release of PGE<sub>2</sub> and LHRH from median eminences (ME) of fed male rats and ones starved for 5 days. Stimulation with potassium (80 m M) induced an equally strong release of PGE<sub>2</sub> and LHRH from the MEs of both fed and starved rats. When PGE<sub>2</sub> (10 <sup>4</sup> M) was added to the superfusion medium, the potassium-stimulated release of LHRH was significantly enhanced in both groups of animals. The results clearly showed that in the terminal region of the hypothalamic LHRH system the release of this hormone and the action of PGE<sub>2</sub> were not altered by starvation. In vivo experiments tested whether the effects of LHRH, PGE<sub>2</sub>, naloxone (NAL), or T on LH secretion were different in intact or castrated male’rats fed or starved for 3 and 5 days. LHRH (250 ng/kg) stimulated the same amount of LH secretion in fed and starved rats. The starvation-induced LH suppression was not due to a dysfunction at the pituitary level. The stimulatory action of PGE<sub>2</sub> (1 mg/kg) on LH was gradually reduced throughout the starvation period. NAL (5 mg/kg) had little, respectively, no effect on LH release on the 3rd or 5th day of starvation. When given simultaneously, NAL did not affect the action of PGE<sub>2</sub> in any of the three nutritional states. The interference of factors other than endorphins or PGE<sub>2</sub> is assumed for starvation-induced suppression of LH secretion. Starvation did not alter the influence of T (ca. 3 ng/ml plasma) on LH secretion at the pituitary level. The stimulatory effect of PGE2 on LH release was completely suppressed by T in fed, as well as in castrated rats starved for 3 or 5 days.

          Related collections

          Author and article information

          S. Karger AG
          28 March 2008
          : 39
          : 6
          : 530-537
          Max-Planck-Institute for Psychiatry, Munich, FRG
          124034 Neuroendocrinology 1984;39:530–537
          © 1984 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: 8
          Original Paper


          Comment on this article