scholarly journals High Salt Intake Increases Copeptin but Salt Sensitivity Is Associated with Fluid Induced Reduction of Copeptin in Women

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Irina Tasevska ◽  
Sofia Enhörning ◽  
Philippe Burri ◽  
Olle Melander

This study investigated if copeptin is affected by high salt intake and whether any salt-induced changes in copeptin are related to the degree of salt sensitivity. The study was performed on 20 men and 19 women. In addition to meals containing 50 mmol NaCl daily, capsules containing 100 mmol NaCl and corresponding placebo capsules were administered during 4 weeks each, in random order. Measurements of 24 h blood pressure, body weight, 24 h urinary volume, and fasting plasma copeptin were performed at high and low salt consumption. Copeptin increased after a high compared to low dietary salt consumption in all subjects 3,59 ± 2,28 versus 3,12 ± 1,95 (P= 0,02). Copeptin correlated inversely with urinary volume, at both low (r= −0,42;P= 0,001) and high (r= −0,60;P< 0,001) salt consumption, as well as with the change in body weight (r= −0,53;P< 0,001). Systolic salt sensitivity was inversely correlated with salt-induced changes of copeptin, only in females (r= −0,58;P= 0,017). As suppression of copeptin on high versus low salt intake was associated with systolic salt sensitivity in women, our data suggest that high fluid intake and fluid retention may contribute to salt sensitivity.

2020 ◽  
Author(s):  
Genevieve Alexandria Bell ◽  
Hillary Ellis ◽  
Michael Tordoff

High salt intake has been linked to obesity in humans and rodents, although the direction of causation and underlying mechanisms are unclear. One hypothesis suggests that consuming salt stimulates thirst, which is assuaged by drinking sugar-sweetened beverages, leading to excess energy intake and thus obesity. We attempted to test this hypothesis using a mouse model. Adult male C57BL/6J mice ate semi-synthetic diets with either low (0.56 g Na+/kg diet) or high (5.62 g Na+/kg diet) salt content for 8 weeks. Half the mice fed each diet could drink water; the other half could drink both water and a 16% sucrose solution. Mice fed the high-salt diet with water to drink ingested ~25% more water than did those fed the low-salt diet with water to drink, demonstrating that salt stimulated thirst. However, there was no influence of dietary salt on water or sucrose intake in the groups with access to both water and sucrose. This was probably because sucrose intakes were near-maximal in both groups; mice apparently do not require salt to encourage them to drink sucrose. Dietary salt level had no effect on body weight. Relative to mice that drank only water, those that drank sucrose had a net increase in energy intake but, surprisingly, gained less body weight, perhaps because they consumed too little protein to thrive. In sum, our results do not support the hypothesis that salt increases sugar-sweetened beverage consumption, leading to obesity; however, the simple mouse model used here may not provide a competent test of this hypothesis.


1993 ◽  
Vol 264 (6) ◽  
pp. H1810-H1816 ◽  
Author(s):  
M. A. Boegehold

This study evaluated the influence of high dietary salt intake on nitric oxide (NO) activity in the arteriolar network of rats resistant to salt-induced hypertension. The spinotrapezius muscle microvasculature was studied in inbred Dahl salt-resistant (SR/Jr) rats fed low (0.45%)- or high (7%)-salt diets for 4–5 wk. Arterial pressures were not different between groups at any time during the study. NO synthesis inhibition with NG-nitro-L-arginine-methyl ester (L-NAME) constricted arcade arterioles in low-salt SR/Jr and dilated arcade arterioles in high-salt SR/Jr. Arcade arteriole dilation to acetylcholine (ACh), but not sodium nitroprusside (SNP), was impaired in high-salt SR/Jr. In contrast, transverse and distal arteriole responses to L-NAME, ACh, and SNP were identical in high- and low-salt SR/Jr. These findings indicate that high salt intake, in the absence of increased arterial pressure, suppresses the influence of basal and evoked NO on vascular tone in arcading arterioles, but not in smaller transverse and distal arterioles. Unaltered SNP responses in high-salt SR/Jr suggest that this effect does not involve a change in arteriolar smooth muscle responsiveness to NO.


2017 ◽  
Vol 43 (5) ◽  
pp. 1987-2000 ◽  
Author(s):  
Qiang Li ◽  
Rongbing Jin ◽  
Hao Yu ◽  
Hongmei Lang ◽  
Yuanting Cui ◽  
...  

Background/Aims: Obesity and high salt intake are major risk factors for hypertension and cardiometabolic diseases. Obese individuals often consume more dietary salt. We aim to examine the neurophysiologic effects underlying obesity-related high salt intake. Methods: A multi-center, random-order, double-blind taste study, SATIETY-1, was conducted in the communities of four cities in China; and an interventional study was also performed in the local community of Chongqing, using brain positron emission tomography/computed tomography (PET/CT) scanning. Results: We showed that overweight/obese individuals were prone to consume a higher daily salt intake (2.0 g/day higher compared with normal weight individuals after multivariable adjustment, 95% CI, 1.2-2.8 g/day, P < 0.001), furthermore they exhibited reduced salt sensitivity and a higher salt preference. The altered salty taste and salty preference in the overweight/obese individuals was related to increased activity in brain regions that included the orbitofrontal cortex (OFC, r = 0.44, P= 0.01), insula (r = 0.38, P= 0.03), and parahippocampus (r = 0.37, P= 0.04). Conclusion: Increased salt intake among overweight/obese individuals is associated with altered salt sensitivity and preference that related to the abnormal activity of gustatory cortex. This study provides insights for reducing salt intake by modifying neural processing of salty preference in obesity.


2011 ◽  
Vol 110 (2) ◽  
pp. 468-471 ◽  
Author(s):  
Mirian J. Starmans-Kool ◽  
Alice V. Stanton ◽  
Yun Y. Xu ◽  
Simon A. McG Thom ◽  
Kim H. Parker ◽  
...  

Dietary salt intake is associated with high brachial blood pressure (BP) and increased risk of cardiovascular disease. We investigated whether changes in dietary salt intake are associated with changes in central BP and wave reflection in healthy volunteers. Ten healthy normotensive male volunteers (22–40 yr) participated in a 6-wk double-blind randomized crossover study to compare a low-dietary salt intake (60–80 mmol sodium/day) with a high-salt intake (low salt intake supplemented with 128 mmol sodium/day) on central BP and wave reflection. Brachial and carotid BP, carotid blood flow velocity, forward (Pf) and backward (Pb) pressure, wave intensity, body weight, and urinary electrolyte excretion were measured at the end of each crossover period. High salt intake significantly increased carotid systolic BP [98 (SD 11) vs. 91 mmHg (SD 13), P < 0.01] and increased wave reflection [ratio of backward to forward pressure (Pb/Pf) 0.13 (SD 0.02) vs. 0.11 (SD 0.03), P = 0.04] despite only small effects on brachial BP [114 (SD 9) vs. 112 mmHg (SD 6), P = 0.1]. Urinary sodium excretion and body weight were also increased following high salt intake. High salt intake disproportionately increases central BP compared with brachial BP as a result of enhanced wave reflection. These effects may contribute to the adverse effect of high dietary salt intake on the risk of cardiovascular disease.


Author(s):  
Muhammad M Shaikh ◽  
Ali HZ Alkhayari ◽  
Qusay AK Alabdulsalam ◽  
Khamis AlHashmi ◽  
Sunil K Nadar

Objectives: High salt consumption is a major risk factor for hypertension. Studies have shown dietary salt intake to be high in many parts of the world. The aim of this study was to assess the daily salt consumption by the urban population in Oman and to assess their knowledge and attitudes towards dietary salt. Methods: This was a cross-sectional questionnaire-based study conducted between September to December 2017 in Muscat. We used previously validated questionnaires to assess salt intake and the knowledge and attitudes to salt intake. Results: 345 responses were received out of 500 distributed questionnaires (response rate 69%) of which 300 responses (27.88 + 7.9 years, 53.3% male) were included for analysis. 94% of the participants agreed that lowering salt in diet is important and nearly half the participants said that they were taking measures to reduce salt intake. However, the median salt intake was high at 10.5(7.3-15.1) gm salt/day. 90% of those questioned consume more than the maximum recommended amount of salt per day. Salt intake was significantly higher in females and older age group (>40 years of age), There did not appear to be any correlation between awareness of the dangers of salt intake and the amount consumed. Conclusion: The salt intake in our sampled population in Oman is high and does not depend on knowledge. Strategies should be designed to reduce salt intake by health education and increasing knowledge about complications of high salt intake among the urban population. Keywords: dietaray sodium chloride; knowledge attitudes and practices.


Hypertension ◽  
2021 ◽  
Vol 78 (Suppl_1) ◽  
Author(s):  
Peng Xu ◽  
John J Gildea ◽  
Mahabuba Akhter ◽  
Robert M Carey ◽  
Wei Yue ◽  
...  

Salt sensitivity affects approximately 20% of adults worldwide and has similar mortality and morbidity sequalae as hypertension. Research has focused on the harmful effects of a high salt diet but have not focused on the harmful effects of a low salt diet. Inverse salt sensitive (ISS) individuals require high salt intake in order to maintain a normal blood pressure. Aldosterone increases ENaC and sodium reabsorption via the mineralocorticoid receptor (MR). We previously reported that αENaC was significantly lower in ISS renal tubule cells isolated from urine (uRTC), while these cells showed higher ENaC like activities under trypsin stimulation. We hypothesized that aldosterone may act as a stimulus and play a role in ISS high blood pressure on a low salt diet (LSD). Plasma aldosterone was significantly increased on LSD in all salt study participants, and ISS individuals showed the highest aldosterone level (ISS HS 3.8±0.38, n=26; ISS LS 35±3.38, n=22; SR HS 4.34±0.18, n=180; SR LS 32.62±1.6, n=152; SS HS 4.65±0.35, n=43; SS LS 26.08±2.18, n=38; HS Vs LS, p<0.001, two-way ANOVA). Moreover, both aldosterone and plasma renin activity (PRA) were significantly lower in salt sensitive (SS) individuals on LSD (PRA LS: ISS 6.05±0.87, n=17; SR 5.94±0.36, n=108; SS 4.43±0.57, n=34; p<0.05, one-way ANOVA), indicating LSD was protective to SS individuals. Treatment of uRTCs with 1 μM aldosterone increased MR and αENaC expression in ISS but not in SR (salt resistant) cells (MR: SR VEH 12164±213; SR Aldosterone 12327±128; ISS VEH 12128±40 vs ISS Aldosterone 13506±128, n=3, p<0.001, two-way ANOVA; αENaC: SR VEH 5023±46; SR Aldosterone 4895±55; ISS VEH 4270±21 vs ISS Aldosterone 5013±113, n=3, p<0.001, two-way ANOVA). High salt treatment further decreased MR in ISS but not in SR cells (ISS: 142mM 11066±188 vs 192mM 10425±74; p<0.05, n=3 two-way ANOVA). These results are consistent with the hypothesis that ISS individuals retain excess Na + and exhibit decreased BP when compared to SR or SS individuals under high salt diet, but reabsorb more sodium and exhibit elevated blood pressure under low salt diet. Higher circulating aldosterone and ex-vivo urine derived renal cell aldosterone sensitivity under low salt conditions may be a novel diagnostic test to identify ISS individuals.


2000 ◽  
Vol 279 (1) ◽  
pp. H269-H278 ◽  
Author(s):  
Timothy R. Nurkiewicz ◽  
Matthew A. Boegehold

The purpose of this study was to determine whether endogenous ANG II augments arteriolar myogenic behavior in striated muscle. Because circulating ANG II is decreased during high salt intake, we also investigated whether dietary salt could alter any influence of ANG II on myogenic behavior. Normotensive rats fed low-salt (0.45%, LS) or high-salt (7%, HS) diets were enclosed in a ventilated box with the spinotrapezius muscle exteriorized for intravital microscopy. Dietary salt did not affect resting arteriolar diameters. Microvascular pressure elevation by box pressurization caused greater arteriolar constriction in LS rats (up to 12 μm) than in HS rats (up to 4 μm). The ANG II-receptor antagonists saralasin and losartan attenuated myogenic responsiveness in LS rats but not HS rats. The bradykinin-receptor antagonist HOE-140 had no effect on myogenic responsiveness in LS rats but augmented myogenic responsiveness in HS rats. HOE-140 with the angiotensin-converting enzyme inhibitor captopril attenuated myogenic responsiveness to a greater extent in LS rats than in HS rats. We conclude that endogenous ANG II normally reinforces arteriolar myogenic behavior in striated muscle and that attenuated myogenic behavior associated with high salt intake is due to decreased circulating ANG II and increased local kinin levels.


2012 ◽  
Vol 13 (3) ◽  
pp. 353-359 ◽  
Author(s):  
MA Bayorh ◽  
A Rollins-Hairston ◽  
J Adiyiah ◽  
D Lyn ◽  
D Eatman

Introduction: The upregulation of cyclooxygenase (COX) expression by aldosterone (ALDO) or high salt diet intake is very interesting and complex in the light of what is known about the role of COX in renal function. Thus, in this study, we hypothesize that apocynin (APC) and/or eplerenone (EPL) inhibit ALDO/salt-induced kidney damage by preventing the production of prostaglandin E2 (PGE2). Methods: Dahl salt-sensitive rats on either a low-salt or high-salt diet were treated with ALDO (0.2 mg pellet) in the presence of EPL (100 mg/kg/day) or APC (1.5 mM). Indirect blood pressure, prostaglandins and ALDO levels and histological changes were measured. Results: Cyclooxygenase-2 (COX-2) levels were upregulated in the renal tubules and peritubular vessels after high-salt intake, and APC attenuated renal tubular COX-2 protein expression induced by ALDO. Plasma PGE2 levels were significantly reduced by ALDO in the rats fed a low-salt diet when compared to rats fed a high-salt diet. PGE2 was blocked by EPL but increased in the presence of APC. Conclusions: The beneficial effects of EPL may be associated with an inhibition of PGE2. The mechanism underlying the protective effects of EPL is clearly distinct from that of APC and suggests that these agents can have differential roles in cardiovascular disease.


1984 ◽  
Vol 67 (2) ◽  
pp. 195-203 ◽  
Author(s):  
Christopher S. Wilcox ◽  
William E. Mitch ◽  
Ralph A. Kelly ◽  
Paul A. Friedman ◽  
Paul F. Souney ◽  
...  

1. We investigated the effects of Na+ intake, the renin-angiotensin-aldosterone system and antidiuretic hormone (ADH) on K+ balance during 3 days of frusemide administration to six normal subjects. Subjects received 40 mg of frusemide for 3 days during three different protocols: Na+ intake 270 mmol/day (high salt); Na+ intake 20 mmol/day to stimulate the renin-angiotensin-aldosterone system (low salt); Na+ intake 270 mmol/day plus captopril (25 mg/6 h) to prevent activation of the renin-angiotensin-aldosterone system. In a fourth protocol, a water load was given during high salt intake to prevent ADH release and then frusemide was given. 2. During high salt intake, frusemide increased K+ excretion (UKV) over 3 h, but the loss was counterbalanced by subsequent renal K+ retention so that daily K+ balance was neutral. 3. During low salt intake, the magnitude of the acute kaliuresis following the first dose of frusemide and the slope of the linear relationship between UKV and the log of frusemide excretion were increased compared with that found during the high salt intake. In addition, low salt intake abolished the compensatory renal retention of K+ after frusemide and cumulative K+ balance over 3 days of diuretic administration was uniformly negative (−86 ± 7 mmol/3 days; P < 0.001). 4. Captopril abolished the rise in plasma aldosterone concentration induced by frusemide. The acute kaliuresis after frusemide was unchanged compared with that observed during high salt intake. The compensatory reduction in UKV occurring after the diuretic was slightly potentiated. In fact, captopril given without the diuretic induced a small positive K+ balance. 5. When a water load was given concurrently with frusemide, the acute kaliuresis was >30% lower compared with that seen with frusemide alone, even though the natriuretic response was unchanged. 6. We conclude that: (a) K+ balance is maintained when frusemide is given during liberal Na+ intake because acute K+ losses are offset by subsequent renal K+ retention; (b) this compensatory K+ retention can be inhibited by aldosterone release which could account for the negative K+ balance seen during salt restriction; (c) the short-term kaliuretic response to frusemide is augmented by release of both ADH and aldosterone whereas changes in K+ balance over 3 days of frusemide are dependent on plasma aldosterone concentration.


1987 ◽  
Vol 252 (2) ◽  
pp. H402-H409 ◽  
Author(s):  
E. Miyajima ◽  
R. D. Bunag

To determine whether baroreflex impairment progresses in hypertensive Dahl rats, we recorded reflex responses to drug-induced changes in blood pressure in hypertension-sensitive (DS) and hypertension-resistant (DR) rats maintained on low- or high-salt diets for 7 wk. Chronotropic responses, manifested as either bradycardia for phenylephrine or tachycardia for sodium nitroprusside, were always smaller in awake DS rats on high-salt diet than in any others. When the same rats were later anesthetized, related changes in afferent aortic and efferent splanchnic nerve activity were similarly reduced. Regardless of dietary salt intake, reflex bradycardia elicited by electrical stimulation of aortic nerve afferents was also weaker in DS than in DR rats, but attendant decreases in mean aortic pressure and splanchnic nerve activity did not differ significantly. These results are compatible with an impairment of afferent and central components of the reflex arc. Even though exact sites of dysfunction were not identified, our findings suggest that in hypertensive DS rats high-salt diets may aggravate baroreflex impairment, at least in part, by acting centrally.


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