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: 292/1/H190    most recent 00622.2006v1 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 PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Monahan, K. D. Articles by Ray, C. A. Search for Related Content PubMed PubMed Citation Articles by Monahan, K. D. Articles by Ray, C. A.

Aldosterone impairs baroreflex sensitivity in healthy adults

Pennsylvania State Heart and Vascular Institute, General Clinical Research Center, Pennsylvania State University College of Medicine, Hershey, Pennsylvania

Submitted 12 June 2006 ; accepted in final form 12 August 2006

Animal studies suggest that acute and chronic aldosterone administration impairs baroreceptor/baroreflex responses. We tested the hypothesis that aldosterone impairs baroreflex control of cardiac period [cardiovagal baroreflex sensitivity (BRS)] and muscle sympathetic nerve activity (MSNA, sympathetic BRS) in humans. Twenty-six young (25 ± 1 yr old, mean ± SE) adults were examined in this study. BRS was determined by using the modified Oxford technique (bolus infusion of nitroprusside, followed 60 s later by bolus infusion of phenylephrine) in triplicate before (Pre) and 30-min after (Post) beginning aldosterone (experimental, 12 pmol·kg^–1·min^–1; n = 10 subjects) or saline infusion (control; n = 10). BRS was quantified from the R-R interval-systolic blood pressure (BP) (cardiovagal BRS) and MSNA-diastolic BP (sympathetic BRS) relations. Aldosterone infusion increased serum aldosterone levels approximately fourfold (P < 0.05) and decreased (P < 0.05) cardiovagal (19.0 ± 2.3 vs. 15.6 ± 1.7 ms/mmHg Pre and Post, respectively) and sympathetic BRS [–4.4 ± 0.4 vs. –3.0 ± 0.4 arbitrary units (AU)·beat^–1·mmHg^–1]. In contrast, neither cardiovagal (19.3 ± 3.3 vs. 20.2 ± 3.3 ms/mmHg) nor sympathetic BRS (–3.8 ± 0.5 vs. –3.6 ± 0.5 AU·beat^–1·mmHg^–1) were altered (Pre vs. Post) in the control group. BP, heart rate, and MSNA at rest were similar in experimental and control subjects before and after the intervention. Additionally, neural and cardiovascular responses to a cold pressor test and isometric handgrip to fatigue were unaffected by aldosterone infusion (n = 6 subjects). These data provide direct experimental support for the concept that aldosterone impairs baroreflex function (cardiovagal and sympathetic BRS) in humans. Therefore, aldosterone may be an important determinant/modulator of baroreflex function in humans.

blood pressure; sympathetic; vagus; autonomic nervous system

This article has been cited by other articles:

				T. Matsukawa and T. Miyamoto Does infusion of ANG II increase muscle sympathetic nerve activity in patients with primary aldosteronism? Am J Physiol Regulatory Integrative Comp Physiol, June 1, 2008; 294(6): R1873 - R1879. [Abstract] [Full Text] [PDF]

				K. D. Monahan, D. J. Dyckman, and C. A. Ray Effect of acute hyperlipidemia on autonomic and cardiovascular control in humans J Appl Physiol, July 1, 2007; 103(1): 162 - 169. [Abstract] [Full Text] [PDF]

				K. D. Monahan Effect of aging on baroreflex function in humans Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2007; 293(1): R3 - R12. [Abstract] [Full Text] [PDF]

				S. Moller, J. S. Iversen, J. H. Henriksen, and F. Bendtsen Reduced baroreflex sensitivity in alcoholic cirrhosis: relations to hemodynamics and humoral systems Am J Physiol Heart Circ Physiol, June 1, 2007; 292(6): H2966 - H2972. [Abstract] [Full Text] [PDF]