Background-In essential hypertension, marked restrictions in dietary sodium intake cause in the short-term period an increase in muscle sympathetic nerve traffic (MSNA) and a baroreflex impairment. The present study was set out to assess on a long-term basis the neuroadrenergic and reflex effects of moderate sodium restriction. Methods and Results-In 11 untreated mild to moderate essential hypertensive patients (age 42.0+/-2.6 years, mean+/-SEM), we measured beat-to-beat blood pressure (Finapres), heart rate (ECG), and MSNA (microneurography) at rest and during stepwise intravenous infusions of phenylephrine and nitroprusside. Measurements were performed at regular sodium intake, after 1 and 8 weeks of low-sodium diet (80 mmol NaCl/d), and repeated again at regular sodium intake. After 1 week, urinary sodium excretion was markedly reduced. This was accompanied by a slight blood pressure reduction, no heart rate change, and a significant increase in plasma renin activity, aldosterone, and MSNA (+23.0+/-4.6% P<0.05). Whereas baroreflex heart-rate control was unchanged, baroreflex modulation of MSNA was reduced by 46.8+/-5.1% (P<0.01). At the end of the 8-week low-sodium diet, the neurohumoral and baroreflex responses were similar to the ones observed after 1 week of the dietary intervention. All changes disappeared when regular sodium diet was restored. Conclusions-Thus, a moderate dietary sodium restriction triggers a sympathetic activation and a baroreflex impairment. Maintenance of low-sodium diet for several weeks does not attenuate these adverse adrenergic and reflex effects.
|Citazione:||Grassi, G., Dell'Oro, R., Seravalle, G., Foglia, G., Quarti Trevano, F., & Mancia, G. (2002). Short- and long-term neuroadrenergic effects of moderate dietary sodium restriction in essential hypertension. CIRCULATION, 106(15), 1957-1961.|
|Tipo:||Articolo in rivista - Articolo scientifico|
|Carattere della pubblicazione:||Scientifica|
|Titolo:||Short- and long-term neuroadrenergic effects of moderate dietary sodium restriction in essential hypertension|
|Autori:||Grassi, G; Dell'Oro, R; Seravalle, G; Foglia, G; Quarti Trevano, F; Mancia, G|
|Data di pubblicazione:||ott-2002|
|Appare nelle tipologie:||01 - Articolo su rivista|