Blog
About

0
views
0
recommends
+1 Recommend
1 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found

      Multiple Mechanisms of Activating Ca 2+ Entry in Freshly Isolated Rabbit Aortic Endothelial Cells

      Read this article at

      ScienceOpenPublisherPubMed
      Bookmark
          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.

          Abstract

          In Fura-2-loaded, freshly isolated rabbit aortic endothelial cells the Ca<sup>2+</sup> entry pathway was investigated using the Mn<sup>2+</sup>-quenching technique. Acetylcholine (ACh) interaction with muscarinic receptors activated Mn<sup>2+</sup> influx through the plasma membrane. Sarcoplasmic-endoplasmic reticulum Ca<sup>2+</sup> ATPase blockers such as cyclopiazonic acid (CPA), thapsigargin and BHQ, which block the endoplasmic reticulum Ca<sup>2+</sup> pump and do not interact with receptors, also activated Mn<sup>2+</sup> influx. Mn<sup>2+</sup> influx activated by either ACh or CPA was blocked by the following agents: SKF96365, a receptor-operated Ca<sup>2+</sup> channel (ROC) blocker; NCDC, a PLC and ROC blocker, and genistein, a tyrosine kinase inhibitor. D600, the L-type Ca<sup>2+</sup> channel blocker, had no significant effect on Mn<sup>2+</sup> influx. Caffeine blocked the ACh-induced Ca<sup>2+</sup> release but had no effect on the ACh-induced Mn<sup>2+</sup> influx. Similarly dantrolene, which blocked intracellular Ca<sup>2+</sup> release induced by ACh, did not affect the ACh-activated Mn<sup>2+</sup> influx. These data suggest that ACh can activate Ca<sup>2+</sup> influx without depletion of the ACh-sensitive intracellular Ca<sup>2+</sup> store. It is concluded (1) that in freshly isolated endothelial cells depletion of the intracellular Ca<sup>2+</sup> store is not necessary for ACh-activated Ca<sup>2+</sup> influx, and (2) that receptor activation and intracellular Ca<sup>2+</sup> store depletion may activate the same Ca<sup>2+</sup> entry pathway through parallel mechanisms.

          Related collections

          Author and article information

          Journal
          JVR
          J Vasc Res
          10.1159/issn.1018-1172
          Journal of Vascular Research
          S. Karger AG
          1018-1172
          1423-0135
          1997
          1997
          24 September 2008
          : 34
          : 3
          : 196-207
          Affiliations
          Department of Pharmacology and Therapeutics, The University of British Columbia, Vancouver, Canada
          Article
          159223 J Vasc Res 1997;34:196–207
          10.1159/000159223
          9226301
          © 1997 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: 12
          Categories
          Introduction

          Comments

          Comment on this article