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Universal salt iodization has been adopted by many countries to address iodine deficiency. More recently, salt-reduction strategies have been widely implemented to meet global salt intake targets of5 g/d. Compatibility of the two policies has yet to be demonstrated. This study compares urinary iodine excretion (UIE) according to 24-h urinary sodium excretion, between South Africa (SA) and Ghana; both countries have implemented universal salt iodization, but in Ghana no salt-reduction legislation has been implemented.Participants from the World Health Organization's Study on Global Ageing and Adult Health Wave 3, with survey and valid 24-h urinary data (Ghana, n = 495; SA, n = 707), comprised the sample. Median 24-h UIE was compared across salt intake categories of5, 5-9 and9 g/d.In Ghana, median sodium excretion indicated a salt intake of 10.7 g/d (interquartile range [IQR] = 7.6), and median UIE was 182.4 µg/L (IQR = 162.5). In SA, both values were lower: median salt = 5.6 g/d (IQR = 5.0), median UIE = 100.2 µg/L (IQR = 129.6). UIE differed significantly across salt intake categories (P0.001) in both countries, with positive correlations observed in both-Ghana: r = 0.1501, P0.0011; South Africa: r = 0.4050, P0.0001. Participants with salt intakes9 g/d in SA did not meet the World Health Organization's recommended iodine intake of 150 µg/d, but this was not the case in Ghana.Monitoring and surveillance of iodine status is recommended in countries that have introduced salt-reduction strategies, in order to prevent reemergence of iodine deficiency.

The adverse effects of vasopressin (AVP) in diverse forms of chronic kidney disease have been well described. They depend on the antidiuretic action of AVP mediated by V2 receptors (V2R). Tolvaptan, a selective V2R antagonist, is now largely used for the treatment of patients with autosomal dominant polycystic kidney disease. Another way to reduce the adverse effects of AVP is to reduce endogenous AVP secretion by a voluntary increase in fluid intake. These two approaches differ in several ways, including the level of thirst and AVP. With voluntary increased drinking, plasma osmolality will decline and so will AVP secretion. Thus, not only will V2R-mediated effects be reduced, but also those mediated by V1a and V1b receptors (V1aR and V1bR). In contrast, selective V2R antagonism will induce a loss of fluid that will stimulate AVP secretion and thus increase AVP's influence on V1a and V1b receptors. V1aR is expressed in the luminal side of the collecting duct (CD) and in inner medullary interstitial cells, and their activation induces the production of prostaglandins, mostly prostaglandin E2 (PGE2). Intrarenal PGE2 has been shown to reduce sodium and water reabsorption in the CD and increase blood flow in the renal medulla, both effects contributing to increase sodium and water excretion and reduce urine-concentrating activity. Conversely, non-steroidal anti-inflammatory drugs have been shown to induce significant water and sodium retention and potentiate the antidiuretic effects of AVP. Thus, during V2R antagonism, V1aR-mediated actions may be responsible for part of the diuresis observed with this drug. These V1aR-dependent effects do not take place with a voluntary increase in fluid intake. In summary, while both strategies may have beneficial effects, the information reviewed here leads us to assume that pharmacological V2R antagonism, with resulting stimulation of V1aR and increased PGE2 production, may provide greater benefit than voluntary high water intake. The influence of tolvaptan on the PGE2 excretion rate and the possibility to use somewhat lower tolvaptan doses than presently prescribed remain to be evaluated.

Introduction: Hypertensive patients have impaired sodium excretion. However, the mechanisms are incompletely understood. There is interaction between kidney and adipose tissue. Whether and how adiponectin, one of adipokines, contributes to impaired sodium excretion in hypertension has not been previously investigated. Hypothesis: Adiponectin promotes natriuresis and diuresis and their impairment is involved in hypertension. Methods: We used Wistar-Kyoto (WKY) rats, spontaneously hypertensive rats (SHRs), GRK4g142A>V transgenic mice to test the natriuresis-effect of adiponectin through intrarenal arterial infusion. Renal proximal tubule (RPT) cells, adiponectin knock out (Adipo-/-) mice, mutant plasmid were used. Results: We demonstrate that sodium excretion was reduced in Adipo-/- mice. The intrarenal arterial infusion of adiponectin induced natriuresis and diuresis in WKY rats, which was impaired in SHRs. Adiponectin inhibited Na+-K+-ATPase activity in RPT cells from WKY rats but not from SHRs. Increased adiponectin receptor phosphorylation and subsequent uncoupling from Gai, rather than altered adiponectin receptor expression, were responsible for the loss of adiponectin-mediated inhibition of RPT Na+-K+-ATPase activity, impaired natriuresis and diuresis in SHRs. Mutation of the AdipoR1 phosphorylation site restored its linkage to Gai and the adiponectin-mediated inhibition of Na+-K+-ATPase activity in RPT cells from SHRs. Finally, we identified G protein-coupled receptor kinase 4 (GRK4) as the cause of adiponectin receptor hyper-phosphorylation. GRK4g142A>V transgenic mice replicated the abnormal adiponectin function in SHRs, whereas down-regulation of GRK4 by renal-ultrasound directed siRNA restored the adiponectin-mediated sodium excretion and reduced the blood pressure in SHRs. Conclusions: The stimulatory effect of adiponectin on sodium excretion is impaired in hypertension, which is attributable to increased renal GRK4 expression and subsequent adiponectin receptor hyper-phosphorylation. Targeting GRK4/adiponectin receptor/Gai may restore the impaired adiponectin-mediated sodium excretion in hypertension, thus representing a novel strategy against hypertension.

Timing of food intake has become a critical factor in determining overall cardiometabolic health. We hypothesized that timing of food intake entrains circadian rhythms of blood pressure (BP) and renal excretion in mice. Male C57BL/6J mice were fed ad libitum or reverse feeding (RF) where food was available at all times of day or only available during the 12-h lights-on period, respectively. Mice eating ad libitum had a significantly higher mean arterial pressure (MAP) during lights-off compared to lights-on (113 ± 2 mmHg vs 100 ± 2 mmHg, respectively; P 0.05); however, RF induced a diurnal rhythm of MAP (79 ± 3 mmHg vs 95 ± 2 mmHg, lights-off vs lights-on phase; P, Graphical Abstract Graphical Abstract

Assessing benefit in PoTS can be complex as it is defined not only on the basis of a postural heart rate change but also on symptoms. Symptoms may vary with time which adds complexity. Purely basing an assessment on a postural heart change does not provide the full picture however currently there are no validated questionnaires to assess for symptom change. It is possible to assess some aspects, assessing exercise abilities or sodium excretion for instance. Biomarkers have been investigated but remain experimental.

Sodium intake and compliance with dietary sodium modification are typically assessed using a 24-h urine collection analyzed using flame photometry, but this is inconvenient. Spot urine samples have been investigated as alternatives to 24-h collections, but their accuracy is poor. Since sodium and chloride are present in equal concentrations in dietary salt, chloride test strips may provide a suitable proxy for at-home measurement of urine sodium concentrations. We aimed to determine whether (i) chloride test strips provide a reliable measure of urinary sodium compared to the gold standard flame photometry and (ii) multiple spot samples accurately reflect 24-h urine sodium. We recruited 43 participants (19 males) aged 23.6 ± 0.6 years to complete multiple consecutive spot samples (morning and evening) along with a 24-h urine sodium collection. Urine 24-h sodium estimates using chloride test strips (114.6 ± 7.5 mmol/day) were highly correlated (r = 0.900, p 0.0001) with flame photometry (121.1 ± 7.7 mmol/day) with a bias of -6.53 ± 22.2 mmol/day. Use of a three-spot sample average (both morning and evening spot samples) with a correction factor applied (122.9 ± 4.1 mmol/day) provided a good approximation of 24-h sodium measured by flame photometry (125.6 ± 9.0 mmol/day), with a bias of -2.55 ± 43.9 mmol/day. Chloride test strips applied to a 24-h urine collection provide a highly accurate measure of urinary sodium excretion, permitting convenient at-home sample collection and analysis. Their application to multiple spot samples provides a reasonable approximation of sodium excretion that can be used to conveniently monitor attempts at dietary sodium manipulation, without the inconvenience of completing a 24-h urine sample.

Introduction: Hypertension predisposes to atrial fibrillation (AF) – a major risk factor for ischaemic stroke. Since a high dietary salt consumption is associated with hypertension, we investigated the association between urinary sodium excretion as a marker for dietary sodium intake and risk of new-onset AF in community-dwelling adults. Method: The UK Biobank includes 40- to 69-year-old British residents recruited 2006–2010. Participants were divided into sex-specific quintiles according to 24-hour sodium excretion estimated based on spot samples with the Kawasaki equation. We excluded participants with AF at baseline. Cox regression adjusted for cardiovascular risk factors was used to assess associations with risk of AF, using the third quintile as reference. Results: A total of 257 545 women and 215 535 men were included. During up to 10 years' follow-up, 2221 women and 3751 men were diagnosed with AF. There was a tendency for an increased risk of AF in the lowest and highest quintiles of estimated daily salt intake in both women and men. In the fully adjusted model, significant associations were seen amongst men in the lowest and highest quintiles of sodium excretion (hazard ratio, HRQv1, 1.20; 95% CI, 1.08–1.32, P < 0.001, and HRQv5 1.15, 95% CI, 1.03–1.27, P = 0.011). Conclusion: We found evidence for a U-shaped association between estimated daily salt intake and AF risk amongst men. A suggestive J-shaped association in women was not statistically confirmed, but analyses were likely underpowered. Our results suggest that above a certain physiological minimum level progressively higher salt intake is associated with increasing risk of AF. (Less)

Background: Premenopausal women have a lower risk of hypertension compared to age-matched men and postmenopausal women. P2Y2 and P2Y4 purinoceptor can be considered potential contributors to hypertension due to their emerging roles in regulating renal tubular Na+ transport. Activation of these receptors inhibits epithelial Na+ channel activity (ENaC) via a phospholipase C (PLC)-dependent pathway resulting in natriuresis. We recently reported that activation of P2Y2 and P2Y4 receptors in the renal medulla by UTP promotes natriuresis in male and ovariectomized (OVX) rats, but not in ovary-intact females. This led us to hypothesize that ovary-intact females have greater basal renal medullary activity of P2 (P2Y2 and P2Y4) receptors regulating Na+ excretion compared to male and OVX rats. Methods: To test our hypothesis, we determined (i) the effect of inhibiting medullary P2 receptors by suramin (750 μg/kg/min) on urinary Na+ excretion in anesthetized male, ovary-intact female and OVX Sprague Dawley rats, (ii) mRNA expression and protein abundance of P2Y2 and P2Y4 receptors and (iii) mRNA expression of their downstream effectors (PLC-1d and ENaCa) in renal inner medullary tissues obtained from these three groups. We also subjected cultured mouse inner medullary collecting duct cells (segment 3, mIMCD3) to different concentrations of 17ß-estradiol (E2, 0, 10, 100 and 1000 nM) to test whether E2 increases mRNA expression of P2Y2 and P2Y4 receptors.Results: Acute P2 inhibition attenuated urinary Na+ excretion in ovary-intact females, but not in male or OVX rats. We found that P2Y2 and P2Y4 mRNA expression was higher in the inner medulla from females compared to males or OVX. Inner medullary lysates showed that ovary-intact females have higher P2Y2 receptor protein abundance, compared to males, however, OVX did not eliminate this sex difference. We also found that E2 dose-dependently upregulated P2Y2 and P2Y4 mRNA expression in mIMCD3. Conclusion: These data suggest that ovary-intact females have enhanced P2Y2 and P2Y4-dependent regulation of Na+ handling in the renal medulla, compared to male and OVX rats. We speculate that the P2 pathway contributes to facilitated renal Na+ handling in premenopausal females.

Among ~25% of patients with essential hypertension (EH), circulating endogenous ouabain (EO) and aldosterone (Aldo) are typically coelevated and their BP is especially salt-sensitive (SS). We probed for exaggerated natriuresis in a large cohort (712) of hypertensive patients that underwent an acute 2hr (T 120 ) load with saline (0.9%/2 L). Results: Using a quartiles analysis of sodium excretion, the 4th quartile subgroups showed higher SBP and DBP at T 120 , and at 2 hrs recovery (T 240 ). Fractional sodium excretion (FE Na) was significantly higher during loading and recovery in the 4 th quartile subgroup. Plasma Aldo was suppressed after saline in all subgroups as expected. SS patients showed an increased EO. In the 4 th quartiles EO was elevated at baseline and after saline (see figure), p Manova > 0.001 and the urinary Na/K ratio output was higher. Further, increases in plasma Na + were greater in the 4 th quartile group (1.91 ± 0.15 vs 0.83 ± 0.13 mM, p

Urea is the most abundant and the largest contributing factor for urine osmolality. Urinary urea excretion is highly interrelated with dietary protein intake. Accordingly, an increase of urinary urea excretion due to high protein diet may lead to urea-induced osmotic diuresis. This study aims to explore the association between nocturnal polyuria (NP) and urea. This is a post hoc analysis of a prospective observational study of subjects who completed a renal function profile between October 2011 and February 2015 (n = 170). Each subject underwent a 24 h urine collection, which included 8 urine samples collected at 3 h intervals. Urine volume, osmolality, creatinine, urea and sodium were determined. Urinary urea excretion was used to estimate dietary protein intake. Compared to the control group, subjects with NP exhibited significantly higher nighttime urea and sodium excretion. Estimated evening dietary protein intake was correspondingly significantly higher amongst the NP subgroup. Nighttime diuresis rate was positively associated with age and nighttime free water clearance, creatinine clearance, sodium excretion, and urea excretion in NP subjects. Therefore, increased nocturnal urinary urea excretion may reflect an additional important mediator of nocturia owing to excess nocturnal urine production.

BackgroundThe study was designed to estimate daily salt intake, its discretionary use in healthy individuals and to validate three common methods for salt estimation in Pakistani population.MethodsInformation on demography and discretionary salt use was collected healthy adults (>18 years) along with a blood sample, spot urine sample and 24 hours urine samples. Sodium, chloride, potassium levels and serum creatinine were measured using standard methods. For daily salt estimation, three common methods i.e. INTERSALT, Tanaka and Kawasaki were validated for their applicability in local settings.ResultsOverall 24 h sodium excretion was 158 mmol/l indicating intake of 8.64 (±4.43) grams salt per day which was significantly associated with male gender (p. ConclusionDaily intake of salt was high than recommended by the WHO. Findings showed that none of the three methods could be used for estimating daily intake of salt in local settings of Pakistan.

Background The novel estrogen receptor, G‐protein–coupled estrogen receptor ( GPER ), is responsible for rapid estrogen signaling. GPER activation elicits cardiovascular and nephroprotective effects against salt‐induced complications, yet there is no direct evidence for GPER control of renal Na + handling. We hypothesized that GPER activation in the renal medulla facilitates Na + excretion. Methods and Results Herein, we show that infusion of the GPER agonist, G1, to the renal medulla increased Na + excretion in female Sprague Dawley rats, but not male rats. We found that GPER mRNA expression and protein abundance were markedly higher in outer medullary tissues from females relative to males. Blockade of GPER in the renal medulla attenuated Na + excretion in females. Given that medullary endothelin 1 is a well‐established natriuretic factor that is regulated by sex and sex steroids, we hypothesized that GPER activation promotes natriuresis via an endothelin 1–dependent pathway. To test this mechanism, we determined the effect of medullary infusion of G1 after blockade of endothelin receptors. Dual endothelin receptor subtype A and endothelin receptor subtype B antagonism attenuated G1‐induced natriuresis in females. Unlike males, female mice with genetic deletion of GPER had reduced endothelin 1, endothelin receptor subtype A, and endothelin receptor subtype B mRNA expression compared with wild‐type controls. More important, we found that systemic GPER activation ameliorates the increase in mean arterial pressure induced by ovariectomy. Conclusions Our data uncover a novel role for renal medullary GPER in promoting Na + excretion via an endothelin 1–dependent pathway in female rats, but not in males. These results highlight GPER as a potential therapeutic target for salt‐sensitive hypertension in postmenopausal women.

Several estimating equations for predicting 24-h urinary sodium (24-hUNa) excretion using spot urine (SU) samples have been developed, but have not been readily available to Chinese populations. We aimed to compare and validate the six existing methods at population level and individual level. We extracted 1671 adults eligible for both 24-h urine and SU sample collection. Mean biases (95% CI) of predicting 24-hUNa excretion using six formulas were 58.6 (54.7, 62.5) mmol for Kawasaki, &minus, 2.7 (&minus, 6.2, 0.9) mmol for Tanaka, &minus, 24.5 (&minus, 28.0, &minus, 21.0) mmol for the International Cooperative Study on Salt, Other Factors, and Blood Pressure (INTERSALT) with potassium, &ndash, 26.8 (&minus, 30.1, &minus, 23.3) mmol for INTERSALT without potassium, 5.9 (2.3, 9.6) mmol for Toft, and &minus, 24.2 (&minus, 27.7, &minus, 20.6) mmol for Whitton. The proportions of relative difference &gt, 40% with the six methods were nearly a third, and the proportions of absolute difference &gt, 51.3 mmol/24-h (3 g/day salt) were more than 40%. The misclassification rate were all &gt, 55% for the six methods at the individual level. Although the Tanaka method could offer a plausible estimation for surveillance of the population sodium excretion in Shandong province, caution remains when using the Tanaka formula for other provincial populations in China. However, these predictive methods were inadequate to evaluate individual sodium excretion.

Objective: To investigate if the low sodium intake is associated with the plasma carnitine and acylcarnitine profile in children with vasovagal syncope (VVS).Materials and Methods: Twenty-six children suffering from VVS were recruited in the present study and divided into a group of low urinary sodium excretion or a group of normal urinary sodium excretion according to the excretion of 24-h urinary sodium 0.05). Concentrations of plasma tiglylcarnitine (C5:1), hydroxyhexadecanoylcarnitine (C16OH), hydroxyoctadecanoylcarnitine (C18OH), and carnitine C22 were significantly higher in the group of low urinary sodium excretion than in the group of normal urinary sodium excretion (all p-values = 0.048); moreover, they were all negatively correlated with 24-h urinary sodium levels (all p-values = 0.016). There were no differences between the two groups in other acylcarnitines or free carnitine.Conclusions: Reduced excretion of 24-h urinary sodium is associated with a disturbed plasma acylcarnitine profile in children with VVS. The findings suggest that restricted sodium intake-induced disturbance of plasma acylcarnitines and related cellular energy metabolism might be involved in the pathogenesis of VVS in children.

Context High dietary salt intake is known to aggravate arterial hypertension. This effect could be of particular relevance in the setting of primary aldosteronism (PA), which is associated with cardiovascular damage independent of blood pressure levels. The aim of this study was to determine the impact of therapy on salt intake in PA patients. Patients and Methods A total of 148 consecutive PA patients (66 with unilateral and 82 with bilateral PA) from the database of the German Conn’s Registry were included. Salt intake was quantified by 24-hour urinary sodium excretion before and after initiation of PA treatment. Study design Observational longitudinal cohort study. Setting Tertiary care hospital. Results At baseline, unilateral PA patients had a significantly higher urinary sodium excretion than patients with bilateral disease (205 vs 178 mmol/d, P = 0.047). Higher urinary sodium excretion correlated with an increased cardiovascular risk profile including proteinuria, impaired lipid, and glucose metabolism and was associated with higher daily doses of antihypertensive drugs to achieve blood pressure control. In unilateral disease, urinary sodium excretion dropped spontaneously to 176 mmol/d (P = 0.012) 1 year after unilateral adrenalectomy and remained low at 3 years of follow-up (174 mmol/d). In contrast, treatment with mineralocorticoid receptor antagonists (MRA) in bilateral PA patients was not associated with a significant change in urinary sodium excretion at follow-up (179 mmol/d vs 183 mmol/d). Conclusion PA patients consuming a high-salt diet, estimated based on urinary sodium excretion, respond to adrenalectomy with a significant reduction of salt intake, in contrast to MRA treatment.

Background The regulation of sodium excretion is important in the pathogenesis of hypertension and salt sensitivity is predictive of cardiovascular events and mortality. C57Bl/6 and BALB /c mice have different blood pressure sensitivities to salt intake. High salt intake increases blood pressure in some C57Bl/6J mouse strains but not in any BALB /c mouse strain. Methods and Results We determined the cause of the difference in salt sensitivity between C57Bl/6 and BALB /c mice. Basal levels of superoxide and H 2 O 2 were higher in renal proximal tubule cells ( RPTC s) from BALB /c than C57Bl/6J mice. High salt diet increased H 2 O 2 production in kidneys from BALB /c but C57Bl/6J mice. High sodium concentration (170 mmol/L) in the incubation medium increased H 2 O 2 levels in BALB /c‐ RPTC s but not in C57Bl/6J‐ RPTC s. H 2 O 2 (10 μmol/L) treatment decreased sodium transport in RPTC s from BALB /c but not C57Bl/6J mice. Overexpression of catalase in the mouse kidney predisposed BALB /c mice to salt‐sensitive hypertension. Conclusions Our data show that the level of salt‐induced H 2 O 2 production negatively regulates RPTC sodium transport and determines the state of salt sensitivity in 2 strains of mice. High concentrations of antioxidants could prevent H 2 O 2 production in renal proximal tubules, which would result in sodium retention and increased blood pressure.

Predhipertenzija je nezavisni čimbenik rizika arterijske hipertenzije (AH) i kardiovaskularnoga rizika (KVR). Predhipertoničari (PHT) su heterogena skupina za koje još ne postoje jasni biljezi za stratifikaciju rizika. Uromodulin (UM) je urinarni protein za koji postoje dokazi o povezanosti s AH. Plan ovog istraživanja je bio analizirati vrijednost UM i utjecaj na obilježja KMAT-a u osoba s PHT mlađih od 45 godina. Cilj nam je bio istražiti utjecaj kliničkih obilježja, unosa kuhinjske soli, bubrežne funkcije te drugih čimbenika KVR na UM i povezanost s arterijskim tlakom (AT) te ocijeniti njegovo dijagnostičko i prognostičko značenje u predhipertenziji. Istraživanje je bilo presječno, opservacijsko i usporedno, a uključeno je 326 ispitanika koji su kategorizirani prema JNC-7 klasifikaciji u normotoničare (NT), PHT i hipertoničare (HT). Svim ispitanicima je uzeta anamneza, učinjen je fizikalni pregled i antropometrijska mjerenja te su uzeti uzorci krvi i urina za laboratorijske analize. U podskupina od 175 ispitanika učinjeno na je anliza 24-satnoga urina te KMAT i UZV srca. Nije utvrđena razlika u vrijednostima UM kod PHT u odnosu na NT i HT niti povezanost s . ordinacijskim AT, ali je postojala dvosmjerna povezanost s parametrima KMAT-a u svim skupinama ispitanika. Uočena je povezanost UM s dobi, opsegom struka, parametrima metabolizma glukoze i lipida, unosom kuhinjske soli, serumskim i urinarnmh parametarima bubrežne funkcije te KMAT-om i UZV srca. Univarijatnom analizom dokazan je utjecaj navedenih parametara na UM, no nakon multivarijatne regresijske analize ostao je značaj za natriuriju i albuminuriju u cijeloj skupini, te dob, kaliuriju, noćnu srčanu frekvenciju i debljinu interventrikularnoga septuma u skupini PHT. Pored toga, uočena je povezanost UM s ukupnim KVR u cijeloj i skupini PHT te pokazateljima hipertenzivnoga oštećenja ciljnih organa. Nije utvrđen dijagnostički značaj UM za nastanak predhipertenzije i arterijske hipertenzije, ali je utvrđena dijagnostička vrijednost u procjeni ukupnoga KVR u cijeloj skupini ispitanika. Iako nije dokazan dijagnostički značaj UM u predhipertenziji, u ovom istraživanju je potvrđena povezanost UM s početnim promjenama miokarda i krutosti velikih krvnih žila te dijagnostički značaj u procjeni ukupnoga KVR u PHT., Prehypertension frequently progress to sustained hypertension and it was found to be associated with increased cardiovascular risk. Prehypertenives (PHT) are heterogeneous population, and no reliable biomarker was identified for risk stratification. Uromodulin (UM) is a urinary glycoprotein associated with risk for arterial hypertension. The goal of our research was to analyse uromodulin values and association with ABPM parameters in PHT younger than 45 years. Additionally, we analyzed relationship of UM with salt intake, kidney function and heart remodelling. Finally, we analyzed impact of UM on global cardiovascular risk (FRS). The research was cross-sectional, observational and comparative study. 326 subjects were enrolled and categorised according to the JNC 7 classification into normotensives (NT), prehypertensives (PHT), and hypertensives (HT). We have taken medical history of all participants, they were physically examined, fasting blood was drawn and urine samples were collected. In subgroup of 175 participants ABPM parameters and echocardiogram were performed. We failed to find significant difference in the level of UM among the blood pressure (BP) categories. UM was not associated with BP values, but association with ABPM parameters was observed. UM correlated with age, waist circumference, salt intake, glucose and lipid metabolism and serum and urinary renal function markers. UM was associated with early signs of heart remodelling and diastolic dysfunction, as well as with arterial stiffness. Furthermore, UM was related to increased global cardiovascular risk independently of BP.

Background. Pregnancy-induced hypertension (PIH) remains a major cause of morbidity and mortality in pregnancy worldwide. This study was designed to study the blood pressure-lowering effect of resveratrol (RES) in a salt-induced hypertensive pregnant rat model. Methods. Forty female Sprague Dawley (SD) rats were randomized into 4 groups: Normal Preg (0.9% salt diet), Normal Preg + RES (0.9% salt diet plus daily oral RES for 4 weeks), Salt Preg (8% salt diet), and Salt Preg + RES (8% salt diet plus daily oral RES for 4 weeks). Noninvasive blood pressure was recorded on gestational days 7 and 14. On the gestational day 19, foetuses were weighed, and blood and urine samples were harvested for electrolytes and biochemical assays. Results. RES significantly reduced SBP, DBP, and MAP on gestational days 7 and 14 in the Salt Preg + RES group compared to the Salt Preg group (all P<0.05). Compared to the Salt Preg group, the foetal weight, serum NO level, urinary sodium, and 24 hour urine volume were significantly increased in the Salt Preg + RES group (all P<0.05). On the contrary, the levels of serum urea, serum creatinine, and urinary protein were significantly decreased in the Salt Preg + RES group compared to the Salt Preg group (all P<0.05). Conclusions. RES decreases blood pressure in a hypertensive pregnant rat model. Increasing sodium excretion and serum nitric oxide level might be, at least part of, the underlying mechanisms.

Introduction:sympathetic and Renin-Angiotensin-Aldosterone systems play crucial roles in blood pressure response to increased salt intake. This study investigated the effects of angiotensin receptor blocker (ARB) and sympathetic excitation on the responses of blood pressure (BP) and peripheral vascular resistance (PVR) in salt loaded normotensive (NT) and hypertensive (HT) Nigerian subjects. Methods:16 NT and 14 HT participants, that were age-matched [39.9 ± 1.3 vs 44.1±2.1yrs (P= 0.10)], underwent 5 days each of oral administration of 200mmol NaCl, and 200mmol NaCl + 50mg Losartan, preceded by a baseline control condition. BP and PVR responses to 30% Maximum Voluntary Contraction (MVC) of handgrip (HG) for one minute were determined at baseline, after salt load and after salt + Losartan. Data were presented as Mean ± SEM, and analyzed with two-way ANOVA and paired t-test, with P

Background: Application of low salt diet interventions to reduce health complaints and the risk of heart disease in hemodialysis patients. Method: Search related articles through scientific publications by entering keywords in the PubMed, ScienceDirect, and Google Scholar databases Results: From the 6 articles reviewed, the low salt diet intervention gave changes to systolic and diastolic blood pressure, provided a change in the level of sodium excretion, changes in quality of life and had self efficacy against salt reduction. Conclusion: It is important for nurses, especially hemodialysis nurses, to optimize education regarding the importance of a low-salt diet of less than 2 grams per day through food and beverages consumed, or in the process of preparing and cooking food.

Objective This study was performed to evaluate the association between urinary sodium excretion and coronary heart disease (CHD) in hospitalized elderly patients in China. Methods The 24-h urinary excretion specimens of 541 patients were collected, and the serum creatinine concentration and urinary sodium/potassium ratio were measured. Associations were explored by multivariate logistic regression analysis. Results The mean 24-h urinary sodium excretion was 200.4 mmol, corresponding to 11.7 g of salt intake. Both of these values were higher in men than in women. The salt intake of 80- to 89-year-old patients was significantly lower than that of 70- to 79-year-old patients. The 24-h urinary sodium excretion and spot urine Na/K ratios were significantly higher in overweight/obese and hypertensive patients. The 24-h urinary sodium excretion of men who smoked was significantly higher than that of women. The spot urine Na/K ratio was significantly higher in patients with cerebral thrombosis. The urinary Na/K ratio, smoking status, and hypertension were independent risk factors for CHD. Conclusions This cross-sectional survey suggests that the Na/K ratio may better represent salt loading than Na excretion alone in studying the association between sodium intake and CHD. There was no association between sodium and CHD prevalence.

It is important to grasp a patient’s daily sodium intake in the management of chronic kidney disease, as sodium intake is widely recommended at 6 g/day or less. There are multiple equations widely known for estimating the daily sodium excretion from a spot urine sample, but these are aimed at healthy people. There are few reports that validate equations in patients with chronic kidney disease. The purpose of this study is to evaluate whether the amount of measured daily sodium excretion from a sample collected for 24-h urine (24HU) is equal to that of using an equation from a spot urine sample (SU) in patients with chronic kidney disease. One hundred sixty-two patients with chronic kidney disease from Kanagawa Prefecture Shiomidai Hospital, Japan and the Jikei University Kashiwa Hospital, Japan participated in the study. Daily sodium excretion was measured from 24HU and compared with it from SU by using the formula according to Tanaka et al. Sodium excretion by 24HU was 2744 mg/day and estimating daily sodium excretion from SU was 3315 mg/day. The coefficient of determination was 0.17 (p

La sindrome metabolica è un fattore di rischio per nefrolitiasi. Questo studio è stato effettuato per valutare il profilo clinico e biochimico di pazienti con nefrolitiasi recidivante da ossalato di calcio e sindrome metabolica. Sono stati arruolati un totale di 526 calcolotici, 184 dei quali con sindrome metabolica, e 214 controlli. I calcolotici con sindrome metabolica hanno mostrato un'escrezione di sodio superiore [media (95% intervallo di confidenza), 196 (176-218) vs 160 (150-168) mmol/24h; p

In most countries, salt intake has been excessive and constitutes one of the main risk factors for disease development, especially hypertension. Factors such as age, gender, sedentary lifestyle, smoking, African descent, obesity, dietary habits and family history of hypertension may be associated with high blood pressure. Studies show a positive association between the excretion of sodium and increased blood pressure. We evaluated the urinary excretion of sodium and associated factors in isolated urine samples of African descendants from remaining Quilombos. We performed a cross-sectional, population-based study with 1162 African descendants living in remaining quilombos in Alcântara, Maranhão, Brazil. Demographic, nutritional, clinical and laboratory data were analyzed. Urinary sodium excretion was estimated using the Kawasaki equation. A multivariate linear regression model was used to identify the variables related to sodium excretion. The average age was 37.6 ± 11.8 years and 51.2% were women. The prevalence of hypertension was 21.3%. The average urinary excretion of sodium was high, especially among the hypertensive (217.9 ± 90.1 vs. 199.2 ± 83.0 mmol/d; p = .002). After an adjusted analysis, only the waist circumference (odds ratios (OR) = 1.16; confidence intervals(CI)95%: 1.03–1.30), triglyceride (OR = 1.13; CI95%: 1.05–1.22), systolic blood pressure (OR = 1.19; CI95%: 1.08–1.32) and Chronic Kidney Disease Epidemiology (CKD-EPI;OR = 1.24; CI95%: 1.15–1.35) remained related to urinary sodium excretion. African descendants had a high rate of sodium excretion, especially among those who had hypertension. Abdominal adiposity, triglyceride and systolic blood pressure levels and renal function by CKD-EPI equation were associated to urinary sodium excretion.

Background Reducing the urinary sodium-to-potassium ratio is important for reducing both blood pressure and risk of cardiovascular disease. Among free-living Japanese individuals, we carried out a randomized trial to clarify the effect of lifestyle modification for lowering urinary sodium-to-potassium ratio using a self-monitoring device. Methods This was an open, prospective, parallel randomized, controlled trial. Ninety-two individuals were recruited from Japanese volunteers. Participants were randomly allocated into intervention and control groups. A month-long dietary intervention on self-monitoring urinary sodium-to-potassium ratio was carried out using monitors (HEU-001F, OMRON Healthcare Co., Ltd., Kyoto, Japan). All participants had brief dietary education and received a leaflet as usual care. Monitors were handed out to the intervention group, but not to the control group. The intervention group was asked to measure at least one spot urine sodium-to-potassium ratio daily, and advised to lower their sodium-to-potassium ratio toward the target of less than 1. Outcomes included changes in 24-hour urinary sodium-to-potassium ratio, sodium excretion, potassium excretion, blood pressure, and body weight in both groups. Results Mean measurement frequency of monitoring was 2.8 times/day during the intervention. Changes in urinary sodium-to-potassium ratio were -0.55 in the intervention group and -0.06 in the control group (P = 0.088); respective sodium excretion changes were -18.5 mmol/24 hours and -8.7 mmol/24 hours (P = 0.528); and corresponding potassium excretion was 2.6 mmol/24 hours and -1.5 mmol/24 hours (P = 0.300). No significant reductions were observed in either blood pressure or body weight after the intervention. Conclusions Providing the device to self-monitor a sodium-to-potassium ratio did not achieve the targeted reduction of the ratio in "pure self-management" settings, indicating further needs to study an effective method to enhance the synergetic effect of dietary programs and self-monitoring practice to achieve the reduction. However, we cannot deny the possibility of reducing sodium-to-potassium ratio using a self-monitoring device.

Renal responses of hypertensive ISIAH and normotensive WAG rats to intragastrically administered isosmotic (0.9 %) and hyperosmotic (2 %) sodium chloride were studied. It was found, that ISIAH rats are characterized by more active water and sodium excretion under these loadings, while different mechanisms underlie the differences in the response of the kidneys of the ISIAH and WAG rats to iso- and hyperosmotic solutions. The greater efficiency of isoosmotic solution excretion in ISIAH rats was related to significant inhibition of sodium reabsorption in the renal tubules during the baroreceptor reflex as a result of reduced basal activity of renal renin-angiotensin system. When hyperosmotic solution was administered, the excretion rate of the load by ISIAH rats was associated with a more rapid development of the reaction, apparently due to the activation of prostaglandin secretion under hyperosmia, because the preliminary infusion of sodium diclofenac blocking their biosynthesis neutralized interstrain differences.

Background: High sodium intake is a major public health concern. Sodium consumption pattern of West Indian population has never been reported before. Objectives: The cross-sectional study assessed sodium intake pattern by considering all possible dietary sources and spot urine sodium estimation among sedentary healthy adults of productive age group (35–55 years). Materials and Methods: Twenty-four-h dietary recall (3 alternative days in a week), food frequency assessment, weighing of table, and cooking salt (n = 218) were performed. Spot urine samples were collected for subset (n = 33) to quantify sodium excretion. Flame photometer “CL 361” was used for food sodium quantification. Results: Men had higher sodium intake than women (3.9 ± 0.4 vs. 3.8 ± 0.4 g/day). Significantly higher sodium intake among men was from processed ready to eat foods (0.8 ± 0.3 vs. 0.6 ± 0.1, P < 0.05) and among women was from cooking and table salt (2.6 ± 0.3 vs. 2.8 ± 0.3, P < 0.001). Lowest quartile (

We hypothesize that delayed natriuresis during mental stress increases the risk of hypertension and other diseases. Our preclinical studies demonstrate an important role for renal endothelin-1 (ET-1) in regulating sodium excretion. Thus, we predict ET-1 may be linked to the delayed stress response in at-risk individuals. We hypothesize that reduced renal ET-1 accounts for derangements in sodium handling under stress, a link never explored in a large human cohort. We determined urinary ET-1 excretion in three observational studies of changes in sodium excretion during mental stress, in which 776 healthy youth (15-19 years) enrolled in a 5-hour protocol (2 hours of rest before and after 1 hour of mental stress). In all studies, 60-minute urine samples were obtained throughout the protocol. Subjects were grouped as retainers (reduced sodium excretion during stress relative to baseline) or excreters (increased sodium excretion during stress relative to baseline). In excreters, ET-1 excretion was significantly increased from baseline to stress (+0.02 pg/min; P .001). In contrast, ET-1 excretion was significantly higher (P = .028) in retainers than excreters at baseline but significantly reduced in retainers under stress (-0.02 pg/min; P .001). ET-1 excretion declined further in retainers during recovery but returned to prestress levels in excreters. Albumin excretion and albumin-to-creatinine ratio were significantly higher in retainers (P = .022, P .001, respectively). Thus, loss of ET-1-dependent natriuresis may account for sodium retention during stress and may predispose retainers to renal diseases such as hypertension and kidney disease.

Brian M Waldman,1,2 Robert A Augustyniak,1–3 Haiping Chen,1,2 Noreen F Rossi1,2,4 1Department of Internal Medicine, 2Department of Physiology, Wayne State University School of Medicine, Detroit, MI, 3Department of Biomedical Sciences, Edward Via College of Osteopathic Medicine-Carolinas, Spartanburg, SC, 4Department of Internal Medicine, John D Dingell Veterans Administration Medical Center, Detroit, MI, USA Abstract: Spontaneous dynamic exercise promotes sympathoinhibition and decreases arterial pressure in two-kidney, one-clip (2K-1C) hypertensive rats. Renal sympathetic nerves stimulate renin secretion and increase renal tubular sodium reabsorption. We hypothesized that daily voluntary wheel running exercise by 2K-1C rats will decrease mean arterial pressure (MAP), plasma angiotensin II (Ang II), and aldosterone as well as normalize urinary sodium and potassium excretion independent of changes in glomerular filtration rate (GFR). Five-week-old male Sprague Dawley rats underwent sham clipping (Sham) or right renal artery clipping (2K-1C). Rats were randomized to standard caging (SED) or cages with running wheels (EX). After 12 weeks, rats were assigned to either collection of aortic blood for measurement of Ang II and aldosterone or assessment of inulin clearances and excretory function. Running distances were comparable in both EX groups. MAP was lower in 2K-1C EX vs 2K-1C SED rats (P