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

      Size Heterogeneity of Affinity-Labeled Estrogen Receptor in the Ram Hypothalamo-Pituitary Axis

      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.


          The presence of multiple monomeric forms of estrogen receptor (ER) has been described in different target tissues. Using [<sup>3</sup>H]tamoxifen aziridine (TA) to covalently label ER and SDS-PAGE to analyze labeled products, ER forms were investigated in ram pituitary and hypothalamus. A major labeled protein of M<sub>r</sub> 60,000-65,000 and a minor species of 50,000-55,000 were found in the pituitary cytosol covalently labeled with [<sup>3</sup>H]TA. In the hypothalamic cytosol, the major TA-labeled species was the M<sub>r</sub> 50,000 form while the 65,000 ER was difficult to detect. Comparison of ER forms after in vitro translocation of the ER complex in purified nuclei of ram pituitary or hypothalamus again showed major ER forms of M<sub>r</sub> 65,000 and 50,000 for the glandular and nervous tissue respectively, suggesting a biological significance for the M<sub>r</sub> 50,000 species. A similar heterogeneity was also observed in male rats used as controls. Moreover, covalent labeling of cytosol from the pars tuberalis/median eminence area showed the presence of ER in this part migrating with a pattern between those of the hypothalamus and the pituitary. The ER heterogeneity was thus demonstrated in the hypothalamo-pituitary axis. The source of this heterogeneity could be: (1) different ER mRNAs according to tissue type; (2) a specific posttranslational processing such as a specific proteolytic activity within the nervous tissue.

          Related collections

          Author and article information

          S. Karger AG
          08 April 2008
          : 57
          : 4
          : 648-653
          aLaboratoire d’Endocrinologie Moléculaire, Unité de Recherches Associées au CNRS, Rennes; bLaboratoire de Physiologie de la Reproduction, INRA, Nouzilly, France
          126420 Neuroendocrinology 1993;57:648–653
          © 1992 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: 6
          Original Paper


          Comment on this article