Short-term changes in dietary sodium intake influence sweat sodium concentration and muscle sodium content in healthy individuals

A series of experiments was conducted to investigate the effects of sodium fertilizers and supplements on the milk production and mammary health of dairy cows. In Expt 1, where sodium fertilizer was applied to productive pastures consisting mainly of the natrophile perennial rye-grass, the herbage sodium content and the milk yield of cows was increased and milk somatic cell count (SCC) reduced. In Expt 2, which used pastures containing less productive, natrophobic grasses and broad-leaved plants in Estonia, sodium fertilizer did not increase herbage sodium content and did not affect milk production or composition. In Expt 3 the sodium content of the diet of individually tethered cows was increased from 1 to either 6 or 11 g/kg dry matter (DM) by adding salt to their restricted feed allowance, and the cows' milk yield was increased by the high level of sodium supplement and milk SCC were reduced by both levels of sodium supplement. The calcium and magnesium status of cows was improved by the sodium supplement. In Expt 4 a low level of supplementary salt was included in the ration of tethered cows to increase the sodium content of the diet from 2 to 3·6 g/kg DM. No effects on milk yield or SCC were found, but the sodium supplement reduced Staphylococcus aureus contamination of the milk, but not the proportion of milk samples infected with Escherichia coli. It was concluded that the optimum dietary sodium concentration for maximum milk yield was greater than the published requirements, and that substantial increases in sodium intake above current requirements also reduced milk SCC.

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The Effects of Short-Term Changes in Sodium Intake on Plasma Marinobufagenin Levels in Patients with Primary Salt-Sensitive and Salt-Insensitive Hypertension

Nutrients ◽

10.3390/nu13051502 ◽

2021 ◽

Vol 13 (5) ◽

pp. 1502

Author(s):

Katarzyna Łabno-Kirszniok ◽

Agata Kujawa-Szewieczek ◽

Andrzej Wiecek ◽

Grzegorz Piecha

Keyword(s):

Blood Pressure ◽

Diastolic Blood Pressure ◽

Sodium Intake ◽

Left Ventricular ◽

Primary Hypertension ◽

Dietary Sodium ◽

Sodium Restriction ◽

Short Term ◽

Salt Loading ◽

Dietary Sodium Restriction

Increased marinobufagenin (MBG) synthesis has been suggested in response to high dietary salt intake. The aim of this study was to determine the effects of short-term changes in sodium intake on plasma MBG levels in patients with primary salt-sensitive and salt-insensitive hypertension. In total, 51 patients with primary hypertension were evaluated during acute sodium restriction and sodium loading. Plasma or serum concentrations of MBG, natriuretic pro-peptides, aldosterone, sodium, potassium, as well as hematocrit (Hct) value, plasma renin activity (PRA) and urinary sodium and potassium excretion were measured. Ambulatory blood pressure monitoring (ABPM) and echocardiography were performed at baseline. In salt-sensitive patients with primary hypertension plasma MBG correlated positively with diastolic blood pressure (ABPM) and serum NT-proANP concentration at baseline and with serum NT-proANP concentration after dietary sodium restriction. In this subgroup plasma MBG concentration decreased during sodium restriction, and a parallel increase of PRA was observed. Acute salt loading further decreased plasma MBG concentration in salt-sensitive subjects in contrast to salt insensitive patients. No correlation was found between plasma MBG concentration and left ventricular mass index. In conclusion, in salt-sensitive hypertensive patients plasma MBG concentration correlates with 24-h diastolic blood pressure and dietary sodium restriction reduces plasma MBG levels. Decreased MBG secretion in response to acute salt loading may play an important role in the pathogenesis of salt sensitivity.

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Sweating Rate and Sweat Sodium Concentration in Athletes: A Review of Methodology and Intra/Interindividual Variability

Sports Medicine ◽

10.1007/s40279-017-0691-5 ◽

2017 ◽

Vol 47 (S1) ◽

pp. 111-128 ◽

Cited By ~ 85

Author(s):

Lindsay B. Baker

Keyword(s):

Interindividual Variability ◽

Sodium Concentration ◽

Sweating Rate ◽

Sweat Sodium Concentration ◽

Sweat Sodium

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Sweat sodium concentration during exercise in the heat in aerobically trained and untrained humans

European Journal of Applied Physiology ◽

10.1007/s00421-011-1911-6 ◽

2011 ◽

Vol 111 (11) ◽

pp. 2873-2881 ◽

Cited By ~ 21

Author(s):

Nassim Hamouti ◽

Juan Del Coso ◽

Juan F. Ortega ◽

Ricardo Mora-Rodriguez

Keyword(s):

Sodium Concentration ◽

Sweat Sodium Concentration ◽

Sweat Sodium ◽

Aerobically Trained

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P4993Tissue sodium concentration emerged as a determinant of hypertrophic vascular remodeling in type 2 diabetes

European Heart Journal ◽

10.1093/eurheartj/ehz746.0171 ◽

2019 ◽

Vol 40 (Supplement_1) ◽

Author(s):

R Schmieder ◽

S Jung ◽

D Kannenkeril ◽

J M Harazny ◽

K Striepe ◽

...

Keyword(s):

Type 2 Diabetes ◽

Vascular Remodeling ◽

Sodium Intake ◽

Structural Parameters ◽

Sodium Concentration ◽

Sodium Content ◽

Resistance Vessels ◽

Retinal Arterioles ◽

Tissue Sodium

Abstract Background Studies describe a linkage between greater sodium intake and higher incidence of organ damage and cardiovascular end points. Sodium intake is usually assessed by measuring 24-hour urinary sodium excretion, which is prone to high fluctuation. For the assessment of tissue sodium a new technique (23Na-MRI) has been developed. We analyzed whether tissue sodium is linked to vascular remodeling of small resistance vessels in patients with type-2 diabetes. Methods In patients with type 2 diabetes we assessed tissue sodium content and vascular structural parameters of the retinal arterioles, since structural changes of resistance vessels (150–300 μm) can be non-invasively and reliably assessed in the retinal circulation by Scanning Laser Doppler Flowmetry (SLDF). Patients with antidiabetic medication were off the therapy (antihypertensives were kept constant) for 4 weeks. The structural parameters of retinal arterioles assessed were outer- and inner diameter (OD & ID), wall thickness (WT), wall-to-lumen ratio (WLR) and wall cross sectional area (WCSA). Tissue sodium content was assessed non-invasively with a 3.0 T clinical MRI system in each patient. Subject placed their lower legs in the center of a 23Na knee coil and sodium content in skin and muscle (musculus triceps surae) were measured. Results In patients with type 2 diabetes (N=52) we observed a significant correlation between tissue sodium content (muscle and skin) and OD, WT and WCSA and a trend has been noticed between muscle sodium content and ID and WLR. Multiple linear regression analysis demonstrated that tissue sodium content is a significant determinant of hypertrophic vascular remodeling as indicated by increased WT and WCSA, independent of age, gender and 24-hour ambulatory diastolic blood pressure. Correlation coefficients Muscle sodium content (mmol/l) Skin sodium content (mmol/l) OD (μmol) r=0.402, p=0.003 r=0.299, p=0.033 ID (μmol) r=0.265, p=0.058 r=0.202, p=0.154 WT (μm) r=0.402, p=0.003 r=0.313, p=0.026 WLR r=0.247, p=0.078 r=0.171, p=0.230 WCSA (μm2) r=0.417, p=0.002 r=0.322, p=0.021 Conclusion With the novel 23Na-MRI technology, we could demonstrate that high tissue sodium concentration is linked to with hypertrophic vascular remodeling of retinal arterioles. Thus, the reduction of tissue sodium content may emerge as a therapeutic target.

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Formulating and evaluating quantitative models of control of sodium stores

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1985.249.5.r624 ◽

1985 ◽

Vol 249 (5) ◽

pp. R624-R633 ◽

Cited By ~ 2

Author(s):

F. H. Daniels ◽

S. Cortell ◽

E. F. Leonard

Keyword(s):

Feedback Control ◽

Sodium Intake ◽

Urinary Sodium Excretion ◽

Sodium Content ◽

The Body ◽

Dietary Sodium ◽

Quantitative Models ◽

Using Data ◽

Available Information ◽

Feedback Control Theory

Numerous factors that influence sodium handling have been identified, and many have been studied in minute detail; however, relatively little information is available regarding either the steady-state relationship between dietary sodium intake and sodium stores or the transient response of intact animals to challenges to sodium homeostasis. In this paper the principles of elementary feedback control theory have been used both to obtain and analyze quantitative models of the feedback control of sodium stores. It has been assumed that the sodium content of the body determines the rate of urinary sodium excretion, and a mass balance has been used to obtain differential equations that describe the dynamics of sodium stores. Both first- and second-order models are considered, and their predictions for both steady states and transients are compared critically with observations from the literature, using data from human studies whenever possible. The results indicate that a relatively simple proportional feedback controller describes most available data well; however, gaps in the available information are identified, and opportunities for future experimental investigation are described.

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