The pharmacokinetics of ouabain associated with toxicity were studied in the cat and the guinea pig both in vivo and in vitro using ouabain-H3. After spinal cord transection a higher dose of ouabain was required to reach the lethal endpoint. This intervention also increased the myocardial and serum levels associated with death. These findings were corroborated in experiments using digitoxin H3. In vitro, substantially higher ouabain tissue contents were associated with a lethal event. In addition, in cats and guinea pigs, the lethal myocardial ouabain content did not change when the infusion rate of ouabain was varied in vivo or the perfusate ouabain concentration was changed in vitro. In vivo, propranolol increases the myocardial ouabain content associated with death to in vitro levels. In vitro, the drug prolongs the time to death by retarding the myocardial uptake of ouabain. These data suggest that the toxic effects of ouabain in the whole animal are largely neural and in the isolated heart, substantially myocardial.
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.