The Calcium Receptor in Health and Disease

Abstract

The recent cloning of a G-protein-coupled, extracellular calcium [(Ca²⁺)_e]-sensing receptor (CaR_G) from the parathyroid, kidney and brain of several species has clarified the molecular mechanisms underlying Ca²⁺-sensing by parathyroid and other cell types. It has long been suspected that such a receptor existed on parathyroid cells, coupled to intracellular second messengers through guanine nucleotide regulatory (G) protein which is able to recognize and respond to (Ca²⁺)_e. Recently, functional screening of a cDNA library constructed from bovine parathyroid mRNA led to the isolation of a 5.3-kb clone expressing maximal Ca²⁺-stimulated Cl^– currents in oocytes. This 5.3-kb cDNA encodes a protein of 1,085 amino acids with three principal predicted structural domains. The CaR_G protein is present in chief parathyroid cells, in C cells of the thyroid, in the cortical thick ascending limb (TAL) and collecting duct of the kidney, and in discrete brain areas. CaR_G may play several physiological roles. It is a central element in the control of both parathyroid and calcitonin secretion by (Ca²⁺)_e. Moreover, functional evidence for its participation in the regulation of renal Ca²⁺ reabsorption in TAL and water reabsorption in the collecting duct has been obtained. Mutations of the CaR_G gene are responsible for hereditary and familial parathyroid disorders, and a decrease in CaR_G expression has been documented in primary and secondary uremic hyperparathyroidism. The expression of CaR_G in several additional organs and tissues allows speculation on the potential involvement in other pathologies.

Journal

Journal ID (publisher-id): EXN

Journal ID (nlm-ta): Nephron Exp Nephrol

Journal ID (doi): 10.1159/issn.1660-2129

Title: Cardiorenal Medicine

Publisher: S. Karger AG

ISSN (Electronic): 1660-2129

Publication date Subscription-year: 1998

Publication date (Print): June 1998

Publication date (Electronic): 22 May 1998

Volume: 6

Issue: 3

Pages: 171-179

Affiliations

Unité 90 INSERM et Département de Néphrologie, Hôpital Necker Paris, France

Article

Publisher ID: 20520 Other ID: Exp Nephrol 1998;6:171–179

DOI: 10.1159/000020520

Copyright statement: © 1998 S. Karger AG, Basel

License:

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

Figures: 2, Tables: 1, References: 76, Pages: 9

Product

Self URI (application/pdf): https://www.karger.com/Article/Pdf/20520

Self URI (text/html): https://www.karger.com/Article/FullText/20520

Self URI (journal page): https://www.karger.com/SubjectArea/Nephrology

Categories

Subject: Editorial Review