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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Increased Dietary Salt Changes Baroreceptor Sensitivity and Intrarenal Renin-Angiotensin System in Goldblatt Hypertension

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Shimoura, Caroline G. ; Lincevicius, Gisele S. ; Nishi, Erika E. ; Girardi, Adriana C. C. ; Simon, Karin A. ; Bergamaschi, Cassia T. ; Campos, Ruy R.
Total Authors: 7
Document type: Journal article
Source: AMERICAN JOURNAL OF HYPERTENSION; v. 30, n. 1, p. 28-36, JAN 2017.
Web of Science Citations: 3

BACKGROUND Renovascular hypertension (2-kidney 1-clip model (2K1C)) is characterized by renin-angiotensin system (RAS) activation. Increased Angiotensin II (AngII) leads to sympathoexcitation, oxidative stress, and alterations in sodium and water balance. AIM The aim of this study was to evaluate whether a discrete increase in sodium chloride intake in 2K1C rats leads to changes in cardiovascular and autonomic function, oxidative stress, and renin angiotensin aldosterone system. METHODS After 4 weeks of induction of hypertension, rats were fed a normal sodium diet (0.4% NaCl) or a high-sodium diet (2% NaCl) for 2 consecutive weeks. Experiments were carried out for 6 weeks after clipping. Mean arterial pressure (MAP), renal sympathetic nerve activity (rSNA), arterial baroreflex control of rSNA, and heart rate (HR) were assessed. Thiobarbituric acid reactive substances and glutathione were measured as indicators of systemic oxidative stress. Angiostensinconverting enzyme (ACE), ACE2, and angiotensinogen were evaluated in clipped and unclipped kidneys as also urinary angiotensinogen and plasma renin activity. Angiotensinogen, plasma renin activity (PRA) and angiotensin-converting enzyme (ACE) and ACE2 in clipped and unclipped kidneys were evaluated. RESULTS High-sodium diet did not change systemic oxidative stress, and basal values of MAP, HR, or rSNA; however, increased renal (-0.7 +/- 0.2 vs. -1.5 +/- 0.1 spikes/s/mm Hg) and cardiac (-0.9 +/- 0.14 vs. -1.5 +/- 0.14 bpm/mm Hg) baroreceptor reflex sensitivity in 2K1C rats. Although there was no alteration in PRA, a high-salt diet significantly decreased urinary angiotensinogen, ACE, and ACE2 expressions in the clipped and unclipped kidneys. CONCLUSIONS Increased arterial baroreceptor control associated with a suppression of the intrarenal RAS in the 2K1C rats on high-salt diet provide a saltresistant effect on hypertension and sympathoexcitation in renovascular hypertensive rats. (AU)

FAPESP's process: 10/04689-5 - Effects of increased sodium intake in renovascular hypertension in rats: role of oxidative stress and the sympathetic nervous system
Grantee:Caroline Gusson Shimoura
Support type: Scholarships in Brazil - Master
FAPESP's process: 13/22522-9 - Role of renal sympathetic nerves on cardiovascular and renal alterations in renovascular hypertension
Grantee:Ruy Ribeiro de Campos Junior
Support type: Regular Research Grants