This Article Full Text Full Text (PDF) All Versions of this Article: 46/6/1321    most recent 01.HYP.0000189183.50301.5cv1 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 Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Coruzzi, P. Articles by Di Rienzo, M. Search for Related Content PubMed PubMed Citation Articles by Coruzzi, P. Articles by Di Rienzo, M. Related Collections Clinical Studies Autonomic, reflex, and neurohumoral control of circulation Hypertension - basic studies Related Article

(Hypertension. 2005;46:1321.)
© 2005 American Heart Association, Inc.

Original Articles

Effects of Salt Sensitivity on Neural Cardiovascular Regulation in Essential Hypertension

Paolo Coruzzi; Gianfranco Parati; Lorenzo Brambilla; Valerio Brambilla; Massimo Gualerzi; Almerico Novarini; Paolo Castiglioni; Marco Di Rienzo

From the Department of Clinical Sciences (P.C., A.N.), University of Parma, Italy, and Fondazione Don C. Gnocchi ONLUS, Parma, Italy; Prevention and Rehabilitation Unit (L.B., V.B., M.G.,), Fondazione Don C. Gnocchi ONLUS, Parma, Italy; Department of Clinical Medicine, Prevention, and Applied Biotechnologies (G.P.), University of Milano-Bicocca and S. Luca Hospital, IRCCS, Istituto Auxologico Italiano, Milan, Italy; and Centro di Bioingegneria (P.C., M.D.), Fondazione Don C. Gnocchi ONLUS, Milan, Italy.

Correspondence to Marco Di Rienzo, Centro di Bioingegneria, Fondazione Don C. Gnocchi, via Capecelatro 66, I-20148 Milano, Italy. E-mail mdirienzo{at}cbi.dongnocchi.it

Salt-sensitive hypertensive subjects, as defined by conventional categorical classification, exhibit alterations of autonomic cardiovascular control. The aim of our study was to explore whether, in hypertensive subjects, the degree of autonomic dysfunction and the level of salt sensitivity are correlated even when the latter is only mildly elevated and displays under-threshold values. Salt sensitivity of 34 essential hypertensive subjects was assessed on a continuous basis by the salt sensitivity index after low- and high-sodium diet. Beat-by-beat finger blood pressure was recorded after each diet period. Autonomic cardiovascular control was evaluated by spectral analysis of blood pressure and pulse interval and by assessment of spontaneous baroreflex sensitivity (sequence technique). Salt sensitivity and baroreflex sensitivity showed a negative relationship during low and high sodium intake, starting from low values of the salt sensitivity index. All spectral indexes of pulse interval, except the ratio between low- and high-frequency powers, were inversely related to salt sensitivity index after high sodium intake. In subjects with lower salt sensitivity, baroreflex sensitivity and pulse interval power in the high-frequency band were higher after high sodium intake than after low sodium intake. In contrast, subjects with a higher salt sensitivity index showed lower values of baroreflex sensitivity and pulse interval power in the high-frequency band, uninfluenced by salt intake. Our results provide the first demonstration of an impairment of parasympathetic cardiac control in parallel with the increase in the degree of salt sensitivity, also in subjects who were not ranked as salt-sensitive by the conventional categorical classification.

Key Words: autonomic nervous system • heart rate • baroreflex • blood pressure • sodium, dietary

Related Article:

Neurogenic Mechanisms and Salt Sensitivity

Heimo Ehmke
Hypertension 2005 46: 1259-1260. [Full Text] [PDF]

This article has been cited by other articles:

				A. J. King, M. Novotny, G. M. Swain, and G. D. Fink Whole body norepinephrine kinetics in ANG II-salt hypertension in the rat Am J Physiol Regulatory Integrative Comp Physiol, April 1, 2008; 294(4): R1262 - R1267. [Abstract] [Full Text] [PDF]

				F. D. McBryde, S.-J. Guild, C. J. Barrett, J. W. Osborn, and S. C. Malpas Cardiovascular Control: Angiotensin II-based hypertension and the sympathetic nervous system: the role of dose and increased dietary salt in rabbits Exp Physiol, September 1, 2007; 92(5): 831 - 840. [Abstract] [Full Text] [PDF]

				P. Coruzzi, M. Gualerzi, E. Bernkopf, L. Brambilla, V. Brambilla, V. Broia, C. Lombardi, and G. Parati Autonomic Cardiac Modulation in Obstructive Sleep Apnea: Effect of an Oral Jaw-Positioning Appliance. Chest, November 1, 2006; 130(5): 1362 - 1368. [Abstract] [Full Text] [PDF]

				A. J. King and G. D. Fink Chronic Low-Dose Angiotensin II Infusion Increases Venomotor Tone by Neurogenic Mechanisms Hypertension, November 1, 2006; 48(5): 927 - 933. [Abstract] [Full Text] [PDF]

				J. M. Wyss Pathways by Which Dietary Salt Affects Blood Pressure and the Nervous System Hypertension, April 1, 2006; 47(4): 638 - 639. [Full Text] [PDF]

				H. Ehmke Neurogenic Mechanisms and Salt Sensitivity Hypertension, December 1, 2005; 46(6): 1259 - 1260. [Full Text] [PDF]