Cultured porcine endothelial cells (EC) released immunoreactive endothelin-1 (ir-endothelin-1) and big endothelin-1 (ir-big endothelin-1) into the medium in a time-dependent way. Reverse-phase high-pressure liquid chromatography coupled with radioimmunoassay showed that the major component of ir-endothelin-1 corresponded to standard endothelin-1 (1-21) and that the major component of ir-big endothelin-1 corresponded to standard big endothelin-1 (porcine 1-39). This release was strongly inhibited by cycloheximide and was, therefore, related to de novo protein synthesis. The release of greater amounts was stimulated by thrombin. The protein kinase C (PKC) inhibitors from two chemical classes, H7 and staurosporine, inhibited release following such stimulation in a relatively dose-dependent way. Neither H7 nor staurosporine affected the basal release of both endothelin-1 and big endothelin-1. Phorbol myristate acetate, which activates PKC and the Ca2+ ionophore A23187, stimulated the release of ir-endothelin-1 and ir-big endothelin-1 in a dose-dependent way, respectively. In addition, the combination of both compounds had a synergistic effect. An inactive enantiomer of phorbol ester, 4α-phorbol-12,13-didecanoate had no effect on the release of ir-endothelin-1 and ir-big endothelin-1. These results suggest that cultured EC release endothelin-1 and big endothelin-1 simultaneously, and that thrombin stimulates this release by a mechanism that probably involves intracellular Ca2+ mobilization and the activation of PKC.

Keywords:
Endothelin-1, Bigendothelin-1, Thrombin, Endothelial cells, Protein kinase C
This content is only available via PDF.
© 1992 S. Karger AG, Basel
1992
Copyright / Drug Dosage / Disclaimer
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.
You do not currently have access to this content.