The regulation of body water during hypotonic expansion (0.6% NaCl; 0.32 ml/kg/min i.v.) of the extracellular space was investigated in 16 male rabbits with different creatinine clearances due to variations in salt intake. In group A (n = 6) sodium intake was 43 mEq/kg/day, in group B (n = 10) 0.6 mEq/kg/day. After 2 weeks the exogenous creatinine clearance in group A averaged 3.85 ± SD 0.62 ml/min/kg, in group B 2.52 ± SD 0.58 ml/min/kg (p < 0.01). Comparable urine flows (group A: 0.40 ± SD 0.064 ml/min/kg, group B: 0.42 ± SD 0.094 ml/min/kg, p > 0.90) were not caused by differences in the free water clearance (group A: ± 0.13 ± SD 0.07 ml/min/kg, group B: ± 0.11 ± SD 0.05 ml/min/kg, p > 0.60), but by a different tubular reabsorption of sodium: group A: 95.1 ± SD 2.11%, group B: 89.4 ± SD 1.53% (p < 0.001). Our results suggest that a physiological mechanism controls the decreased tubular reabsorption of sodium in kidneys with reduced glomerular filtration rates during a rapid hypotonic expansion of the extracellular space.

Keywords:
Body water, Variation in salt intake, Different glomerular filtration rate, Tubular reabsorption of sodium
This content is only available via PDF.
© 1973 S. Karger AG, Basel
1973
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.