HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 289/6/R1687    most recent 00205.2005v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (12) Citing Articles via Google Scholar Google Scholar Articles by Brown, C. M. Articles by Montani, J.-P. Search for Related Content PubMed PubMed Citation Articles by Brown, C. M. Articles by Montani, J.-P.

WATER AND ELECTROLYTE HOMEOSTASIS

Cardiovascular responses to water drinking: does osmolality play a role?

Department of Medicine, Division of Physiology, University of Fribourg, Switzerland

Submitted 24 March 2005 ; accepted in final form 14 July 2005

Water drinking activates the autonomic nervous system and induces acute hemodynamic changes. The actual stimulus for these effects is undetermined but might be related to either gastric distension or to osmotic factors. In the present study, we tested whether the cardiovascular responses to water drinking are related to water's relative hypoosmolality. Therefore, we compared the cardiovascular effects of a water drink (7.5 ml/kg body wt) with an identical volume of a physiological (0.9%) saline solution in nine healthy subjects (6 male, 3 female, aged 26 ± 2 years), while continuously monitoring beat-to-beat blood pressure (finger plethysmography), cardiac intervals (electrocardiography), and cardiac output (thoracic impedance). Total peripheral resistance was calculated as mean blood pressure/cardiac output. Cardiac interval variability (high-frequency power) was assessed by spectral analysis as an index of cardiac vagal tone. Baroreceptor sensitivity was evaluated using the sequence technique. Drinking water, but not saline, decreased heart rate (P = 0.01) and increased total peripheral resistance (P < 0.01), high-frequency cardiac interval variability (P = 0.03), and baroreceptor sensitivity (P = 0.01). Neither water nor saline substantially increased blood pressure. These responses suggest that water drinking simultaneously increases sympathetic vasoconstrictor activity and cardiac vagal tone. That these effects were absent after drinking physiological saline indicate that the cardiovascular responses to water drinking are influenced by its hypoosmotic properties.

baroreceptors; blood pressure; cardiac output; heart rate; autonomic nervous system

This article has been cited by other articles:

				D. Gentilcore, J. H. Meyer, C. K. Rayner, M. Horowitz, and K. L. Jones Gastric distension attenuates the hypotensive effect of intraduodenal glucose in healthy older subjects Am J Physiol Regulatory Integrative Comp Physiol, August 1, 2008; 295(2): R472 - R477. [Abstract] [Full Text] [PDF]

				D. Negoianu and S. Goldfarb Just Add Water J. Am. Soc. Nephrol., June 1, 2008; 19(6): 1041 - 1043. [Full Text] [PDF]

				C. M. Brown, A. G. Dulloo, G. Yepuri, and J.-P. Montani Fructose ingestion acutely elevates blood pressure in healthy young humans Am J Physiol Regulatory Integrative Comp Physiol, March 1, 2008; 294(3): R730 - R737. [Abstract] [Full Text] [PDF]

				V. L. Brooks, K. L. Freeman, and Y. Qi Time course of synergistic interaction between DOCA and salt on blood pressure: roles of vasopressin and hepatic osmoreceptors Am J Physiol Regulatory Integrative Comp Physiol, December 1, 2006; 291(6): R1825 - R1834. [Abstract] [Full Text] [PDF]

				V. R. Antunes, S. T. Yao, A. E. Pickering, D. Murphy, and J. F. R. Paton A spinal vasopressinergic mechanism mediates hyperosmolality-induced sympathoexcitation J. Physiol., October 15, 2006; 576(2): 569 - 583. [Abstract] [Full Text] [PDF]

				S. R. Raj, I. Biaggioni, B. K. Black, A. Rali, J. Jordan, I. Taneja, P. A. Harris, and D. Robertson Sodium Paradoxically Reduces the Gastropressor Response in Patients With Orthostatic Hypotension Hypertension, August 1, 2006; 48(2): 329 - 334. [Abstract] [Full Text] [PDF]