19
views
0
recommends
+1 Recommend
1 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found

      Effects of Sympathetic Blockade and Splenectomy on Cardiac Output Response to Muscular Work in Dogs

      research-article
      ,
      Cardiology
      S. Karger AG
      Propranolol, Practolol, Mecamylamine, Vagotomy, Frank-Starling mechanism

      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

          The effects of splenectomy and sympathetic blockade on cardiac output (Q̇) response to mild to moderate exercise were studied in chloralose-anesthetized vagotomized dogs during electrically-induced muscular work, which increased oxygen consumption (V̇O<sub>2</sub>) 4- to 5-fold. Splenectomy reduced the exercise factor (ΔQ̇/ΔV̇O<sub>2</sub> ratio) from 5.86 ± 0.43 (SE) to 3.30 ± 0.34 (p < 0.001), while left nephrectomy had no effect. The exercise factor was not affected by β-adrenoceptor blockade produced by propranolol or practolol, but was reduced by mecamylamine. The spleen did not increase cardiac output by displacing blood into the general circulation because pulmonary artery wedge pressure did not change during exercise in normal dogs. Furthermore, cardiac output was increased 35 ± 6% after intraportal infusion of splenic venous blood obtained during exercise, whereas arterial blood infusion increased cardiac output only 10%. We conclude that the cardiac output rise during exercise in part is caused by the inotropic action of a splenic noncatecholamine substance, which is released by sympathetic stimulation.

          Related collections

          Author and article information

          Journal
          CRD
          Cardiology
          10.1159/issn.0008-6312
          Cardiology
          S. Karger AG
          0008-6312
          1421-9751
          1977
          1977
          29 October 2008
          : 62
          : 1
          : 21-34
          Affiliations
          Departments of Medicine and Pharmacology, and Cardiovascular Institute, Boston University School of Medicine; Cardiology Department, Medical Service and Thorndike Memorial Laboratories, Boston City Hospital, and Departments of Medicine and Clinical Research, University Hospital, Boston, Mass.
          Article
          169837 Cardiology 1977;62:21–34
          10.1159/000169837
          872152
          82681de2-c6e4-4598-9872-351e4fa048dc
          © 1977 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.

          History
          Page count
          Pages: 14
          Categories
          Paper

          General medicine,Neurology,Cardiovascular Medicine,Internal medicine,Nephrology
          Frank-Starling mechanism,Mecamylamine,Practolol,Vagotomy,Propranolol

          Comments

          Comment on this article