Trimetazidine Protects from Mercury-Induced Kidney Injury.

INTRODUCTION: The presence of mercury in the environment is a worldwide concern. Inorganic mercury is present in industrial materials, is employed in medical devices, is widely used in batteries, is a component of fluorescent light bulbs, and it has been associated with human poisoning in gold mining areas. The nephrotoxicity induced by inorganic mercury is a relevant health problem mainly in developing countries. The primary mechanism of mercury toxicity is oxidative stress. Trimetazidine (TMZ) is an anti-ischemic drug, which inhibits cellular oxidative stress, eliminates oxygen-free radicals, and improves lipid metabolism. The aim of this study was to evaluate whether the administration of TMZ protects against mercuric chloride (HgCl2) kidney damage. METHODS: Adult male Wistar rats received only HgCl2 (4 mg/kg bw, sc) (Hg group, n = 5) or TMZ (3 mg/kg bw, ip) 30 min before HgCl2 administration (4 mg/kg bw, sc) (TMZHg group, n = 7). Simultaneously, a control group of rats (n = 4) was studied. After 4 days of HgCl2 injection, urinary flow, urea and creatinine (Cr) plasma levels, Cr clearance, urinary glucose, and sodium-dicarboxylate cotransporter 1 (NaDC1) in urine were determined. Lipid peroxidation (MDA) and glutathione (GSH) levels were measured in kidney homogenates. RESULTS: Rats only treated with HgCl2 showed an increase in urea and Cr plasma levels, urinary flow, fractional excretion of water, glucosuria, and NaDC1 urinary excretion as compared with the control group and a decrease in Cr clearance. TMZHg group showed a decrease in urea and Cr plasma levels, urinary flow, fractional excretion of water, glucosuria, NaDC1 urinary excretion, and an increase in Cr clearance when compared to the Hg group. Moreover, MDA and GSH levels observed in Hg groups were decreased and increased, respectively, by TMZ pretreatment. CONCLUSION: TMZ exerted a renoprotective action against HgCl2-induced renal injury, which might be mediated by the reduction of oxidative stress. Considering the absence of toxicity of TMZ, its clinical application against oxidative damage due to HgCl2-induced renal injury should be considered. The fact that TMZ is commercially available should simplify and accelerate the translation of the present data "from bench to bedside." In this context, TMZ become an interesting new example of drug repurposing.

High Salt Diet Impacts the Risk of Sarcopenia Associated with Reduction of Skeletal Muscle Performance in the Japanese Population.

The World Health Organization has recommended 5 g/day as dietary reference intakes for salt. In Japan, the averages for men and women were 11.0 g/day and 9.3 g/day, respectively. Recently, it was reported that amounts of sodium accumulation in skeletal muscles of older people were significantly higher than those in younger people. The purpose of this study was to investigate whether the risk of sarcopenia with decreased muscle mass and strength was related to the amount of salt intake. In addition, we investigated its involvement with renalase. Four groups based on age and salt intake ("younger low-salt," "younger high-salt," "older low-salt," and "older high-salt") were compared. Stratifying by age category, body fat percentage significantly increased in high-salt groups in both younger and older people. Handgrip strength/body weight and chair rise tests of the older high-salt group showed significant reduction compared to the older low-salt group. However, there was no significant difference in renalase concentrations in plasma. The results suggest that high-salt intake may lead to fat accumulation and muscle weakness associated with sarcopenia. Therefore, efforts to reduce salt intake may prevent sarcopenia.

Diuretic state affects ascending thin limb tight junctions.

The nephron segments in the inner medulla are part of the urine concentrating mechanism. Depending on the diuretic state, they are facing a large range of extracellular osmolality. We investigated whether water homeostasis affects tubular transport and permeability properties in inner medullary descending thin limb (IMdTL) and ascending thin limb (IMaTL). Three experimental groups of rats under different diuretic states were investigated on metabolic cages: waterload, furosemide-induced diuresis, and control (antidiuresis). Urine production and osmolalities reflected the 3-day treatment. To functionally investigate tubular epithelial properties, we performed experiments in freshly isolated inner medullary thin limbs from these animals. Tubular segments were acutely dissected and investigated for trans- and paracellular properties by in vitro perfusion and electrophysiological analysis. IMdTL and IMaTL were distinguished by morphological criteria. We confirmed absence of transepithelial electrogenic transport in thin limbs. Although diffusion potential measurements showed no differences between treatments in IMdTLs, we observed increased paracellular cation selectivity under waterload in IMaTLs. NaCl diffusion potential was -5.64 ± 1.93 mV under waterload, -1.99 ± 1.72 mV under furosemide-induced diuresis, and 0.27 ± 0.40 mV under control. The corresponding permeability ratio PNa/Cl was 1.53 ± 0.21 (waterload), 1.22 ± 0.18 (furosemide-induced diuresis), and 0.99 ± 0.02 (control), respectively. Claudins are main constituents of the tight junction responsible for paracellular selectivity; however, immunofluorescence did not show qualitative differences in claudin 4, 10, and 16 localization. Our results show that IMaTLs change tight junction properties in response to diuretic state to allow adaptation of NaCl reabsorption.

Excreción urinaria de iodo y sal en población de Buenos Aires, Argentina / Iodine and salt urinary excretion in Buenos Aires population, Argentina / Excreção urinária de iodo e sal na população de Buenos Aires, Argentina

El iodo es un micronutriente esencial escaso en la dieta. Su deficiencia se asocia con bocio y deterioro cognitivo, entre otras manifestaciones. Desde 1967, la sal de mesa es enriquecida en 33 μg de iodo/g de sal. Recientemente, bajo la propuesta "Menos sal, más vida" se ha legislado para reducir la ingesta de los habituales 10-12 g a 5 g de sal por día. Resulta de interés determinar si la ingesta de sal y la de iodo han disminuido y si están relacionadas. Se evaluó la ingesta reciente de iodo y de sal a través de su excreción urinaria (Reacción de Sandel-Kolthoff y de Mohr, respectivamente), en 514 muestras de orina, agrupadas por sexo y grupo etáreo (<20 años, 20-30 años, 30-60 años y >60 años). Se emplearon los criterios recomendados por la OMS para el análisis de los resultados. La mediana en la excreción de iodo para adultos fue 83 μg/L a la vez que el 18% de las muestras presentaron concentraciones de iodo urinario menores de 50 μg/L, valores indicativos de ingesta deficiente. Un muy bajo porcentaje de muestras (3%) mostró valores de iodo urinario excesivos. El promedio de valores urinarios de sal en adultos fue 5,0 g/L. La correlación global entre ambos parámetros fue de 0,76, pero se encontró un valor más alto de correlación dentro de algunos grupos etarios (hasta 0,91).

Iodine is an essential micro-nutrient in the diet. Its deficiency is associated with goiter and cognitive impairment, among other manifestations. Since 1967, salt has been enriched in 33 μg of iodine/g of salt. Recently, under the proposed "Less salt, more life" regulations tend to reduce the daily salt intake from the usual 10-12 g to 5 g. The aim of this study was to determine if salt, and therefore iodine intakes have declined and whether they are related or not. Recent iodine and salt intakes were assessed through urinary excretion (Sandel-Kolthoff reaction and Mohr method respectively), in 514 urine samples, grouped by sex and age range (<20 years, 20-30 years, 30-60 years y >60 years). The criteria recommended by WHO were used to analyze the results. Medium excretion of iodine for adults was 83 ug/L and 18% of the samples presented urinary iodine concentrations lower than 50 μg/L, indicative of poor iodine intake. A very low percentage of samples (3%) showed excessive urinary iodine values. Medium urinary salt values in adults were 5.0 g/L. The global correlation between both parameters, resulted 0.76, but better correlation was found for some age groups (up to 0.91).

O iodo é um micronutriente essencial escasso na dieta. Sua deficiência está associada com bócio e deterioração cognitiva, entre outras manifestações. Desde 1967, o sal é enriquecido em 33 μg de iodo/g de sal. Recentemente sob a proposta "Menos sal, mais vida" legislou-se para reduzir a ingestão de sal dos habituais 10-12 g para 5 g por dia. É de interesse para determinar se a ingestão de sal e a de iodo diminuíram e se estão relacionados. A ingestão recente de iodo e sal foi avaliada através da excreção urinária (Reação de Sandel-Kolthoff e Mohr respectivamente), em 514 amostras de urina, agrupadas por sexo e idade (<20 anos, 20-30 anos, 30-60 anos e>60 anos). Foram utilizados os critérios recomendados pela OMS para a análise dos resultados. A mediana na excreção de iodo para adultos foi 83 ug/L ao mesmo tempo que 18% das amostras apresentaram concentrações de iodo urinário menores de 50 μg/L, valores indicativos da ingestão deficiente. Uma percentagem muito baixa de amostras (3%) mostrou valores de iodo urinário excessivos. A média de valores de sal urinários em adultos foram 5.0 g/l. A correlação global entre os dois parâmetros foi de 0,76, mas se encontrou um valor mais alto de correlação dentro de alguns grupos etários (até 0,91).

The SONG (Salt intake and OrigiN from General foods) Study - A Large-scale Survey of the Eating Habits and Dietary Salt Intake in the Working-age Population.

Objective Dietary salt reduction is important for the prevention and treatment of lifestyle-related diseases, including hypertension. Thus, in order to follow a strict low-salt diet, it is necessary to assess one's salt intake and to become aware of the importance of salt reduction. Methods More than 2,000 employees of a company, who received a periodic health checkup, participated in the present study. They assessed their day-to-day diet-related lifestyle, using the Salt Check Sheet, and we analyzed the correlations among the Salt Check Sheet scores, the daily salt intake (as estimated by a spot urine sample), and the results of the periodic health checkup. Results In the overall survey population, we only found a weak correlation between the salt check scores and the salt intake. In a subgroup analysis, significant correlations between these two variables were observed among untreated hypertensive participants, but not among treated hypertensive participants. We examined the association between 13 individual questionnaire items and the estimated daily salt intake using a multivariate linear regression model and found that only 5 of the 13 questionnaire items were correlated with the daily salt intake. Conclusion We found that a Salt Check Sheet composed of the 5 items that showed a strong correlation with the salt intake might be more useful for periodic health checks of the working-age population.

Blood pressure control status and relationship between salt intake and lifestyle including diet in hypertensive outpatients treated at a general hospital.

The purpose of the present study was to investigate blood pressure (BP) control and salt intake in hypertensive outpatients treated at a general hospital and to examine the relationship between their lifestyles and amount of salt intake. Subjects comprised 429 hypertensive patients (206 males, 223 females, and average age of 71 ± 11 years). We estimated 24-hour salt excretion using spot urine samples and assessed lifestyle using a self-description questionnaire. Average clinic BP and the number of antihypertensive drugs were 132 ± 11/73 ± 8 mmHg and 1.8 ± 0.9, respectively. In all subjects, average estimated salt intake was 9.2 ± 2.8 g/day and the rate of achievement of the estimated salt intake of <6 g/day was 11.2%. In patients with chronic kidney disease or cardiovascular disease, these values were 8.6 ± 2.6 g/day and 15.5%, and 9.1 ± 3.3 g/day and 18.2%, respectively. Estimated salt intake was lower in patients living alone than in those with a family. In a multivariate analysis, estimated salt intake correlated positively with body mass index and negatively with age. Among patients with an excessive salt intake (≥10 g/day), 75.2% answered that they made an effort to reduce their salt intake. The amount of food and processed food consumption correlated with estimated salt intake. In conclusion, the rate of achievement of salt restriction was low in hypertensive patients treated at a general hospital. It may be important to provide data on actual salt intake and guide salt restriction in the individual management of hypertension.

Effect of Intensive Salt-Restriction Education on Clinic, Home, and Ambulatory Blood Pressure Levels in Treated Hypertensive Patients During a 3-Month Education Period.

The authors tested the hypothesis that low-salt diet education by nutritionists would lower blood pressure (BP) levels in treated hypertensive patients. The amount of urinary salt excretion and clinic, home, and ambulatory BP values at baseline and at 3 months were measured in 95 patients with hypertension. After randomization to a nutritional education group (E group, n=51) or a control group (C group, n=44), the C group received conventional salt-restriction education and the E group received intensive nutritional education aimed at salt restriction to 6 g/d by nutritionists. From baseline to the end of the study, 24-hour urinary sodium excretion was significantly lowered in the E group compared with the C group (6.8±2.9 g/24 h vs 8.6±3.4 g/24 h, P<.01). Morning home systolic BP tended to be lowered in the E group (P=.051), and ambulatory 24-hour systolic BP was significantly lowered in the E group (-4.5±1.3 mm Hg) compared with the C group (2.8±1.3 mm Hg, P<.001). Intensive nutritional education by nutritionists was shown to be effective in lowering BP in treated hypertensive patients.

Estimación del consumo de sodio en mujeres adultas a partir del sodio urinario de 24 horas / Estimation of sodium intake in adult women through 24-hour urinary sodium excretion / Estimativa do consumo de sódio emmulheres adultas a partir do sódiourinário de 24 horas

La excreción de sodio en orina de 24 horas es considerado un marcador confiable para obtener el consumo desodio dietético.Objetivos: Estimar consumo de sodio por excreción urinaria de sodio 24 horas, en mujeres adultas concurrentes al Laboratorio 12 de Octubre Dr. Wolfthal-Quilmes- Provincia de Buenos Aires. Conocer variación de la ingesta según la edad y adecuación a recomendaciones de la OMS. Metodología: Estudio transversal retrospectivo, sobre base de datos de mujeres (45 a 65 años), con valores de diuresis y electrolitos urinarios en 24 horas. Variable dependiente: ingesta de sodio (como g ClNa/día); Variables independientes: sodio urinario 24hs (mEq/24hs), edad (en años y categorizada en lustros) y etapa biológica (pre y postmenopausia). La concentración de sodio urinario se obtuvo por método ión selectivo en equipo Tecnolab (Valor referencia:151-210 mEq/24 hs). Para predecir ingesta de sodio se utilizó ecuación de Tanka donde ClNa (g/día) = Nag/d x 100/39,3. Análisis estadístico con SPSS 15.0, calculando media, desvío estándar y cuartilos; ANOVA y correlación de Pearson con p<0,05. Resultados: Se evaluaron 126 mujeres (56,6±5,8 años); ingesta de sodio: 7,1±3,2 g ClNa/día; excreción urinaria de sodio:120,9±55,2 mEq/24hs. Consumo de sodio en cuartil más alto: 8,5 g ClNa/día y en cuartil más bajo: 4,8 g ClNa/día. Se observó correlación negativa entre consumo de sodio y edad (r= - 0,263; p=0,003). No se encontró correlacióncon etapa biológica. Conclusiones: El 68.3% de la muestra no cumple con las recomendaciones actuales de sodio dadas por la OMS de 5 g/día.

The 24-hour urinary sodium excretion is considered a reliable marker for dietary sodium intake. ObjectivesTo estimate the sodium intake through 24-hour urinary sodium excretion in adult women attending the 12 de Octubre-Dr. Wolfthal Laboratory, Quilmes, Buenos Aires Province. To know the sodium intake variations according to age and adequacy to WHO recommendations. MethodologyA retrospective cross-sectional study investigating a women database (45-65 years), with values of diuresis and urinary electrolytes in 24 hours. Dependent variable:sodium intake (g NaCl/day), independent variables: 24-hour urinary sodium excretion (mEq/24hrs), age (in yearsand categorized in five-year periods) and biological stage(pre and postmenopausal women). Urinary sodiumconcentration was determined by using the ion-selective electrode method in Tecnolab equipment (baseline: 151-210 mEq/24 hrs). To predict sodium intake, the Tanaka’sequation was used, where NaCl (g/day) = Na g/d x100/39.3. The statistical analysis was performed usingSPSS 15.0 software, and mean, standard deviation and quartiles values were calculated; ANOVA and Pearson correlation with p <0.05.Results:126 women (56.6 ± 5.8 years) were evaluated, sodiumintake: 7.1 ± 3.2 g NaCl/day, urinary sodium excretion:120.9 ± 55.2 mEq/24hrs. Sodium consumption in the highest quartile: 8.5 gNaCl/day and in the lowest quartile: 4.8 g NaCl/day.A negative correlation was observed between sodium intake and age (r = - 0.263, p = 0.003). There was no correlation with biological stage. Conclusions:68.3% of the study population does not meet current WHO recommendations on sodium consumption of 5g/day.

A excreção de sódio em urina de 24 horas é considerado dietético. Objetivos Estimar o consumo de sódio por excreção urinária de sódio 24 horas, em mulheres adultas que comparecer a mao Laboratório 12 de Octubre Dr. Wolfthal-Quilmes-Província de Buenos Aires. Conhecer variação da ingestão segundo a idade e adequação às recomendações da OMS. Metodologia:Estudo transversal retrospectivo, sobre base de dados de mulheres (45 a 65 anos), com valores de diurese e eletrólitos urinários em 24 horas. Variável dependente: ingestão de sódio (como g ClNa/dia); Variáveis independentes: sódio urinário 24hs (mEq/24hs), idade ( em anos e categorizada em quinquênios) e etapa biológica (pré e pós-menopausa). A concentração de sódio urinário foi obtida através do método íon seletivo em equipamento Tecnolab (Valor referência 151-210 mEq/24 hs). Para predizer a ingestão de sódio foi utilizada a equação de Tanka onde ClNa(g/dia) = Na g/d x 100/39,3. Análise estatística com SPSS®15.0, calculando média, desvio padrão e quartis; ANOVA e correlação de Pearson com p <0,05.Resultados: Foram avaliadas 126 mulheres (56,6±5,8 anos); ingestão de sódio: 7,1±3,2 g ClNa/dia, excreção urinária de sódio:120,9±55,2 mEq/24hs. Consumo de sódio em quartil mais alto: 8,5 g ClNa/dia e em quartil mais baixo: 4,8 g ClNa/dia.Observou-se correlação negativa entre consumo de sódio e idade (r= - 0,263; p=0,003). Não se encontrou correlação com etapa biológica.Conclusões68.3% da amostra não cumprem com as recomendações atuais de sódio dadas pela OMS de 5 g/dia.

The effect of saponins from Ampelozizyphus amazonicus Ducke on the renal Na+ pumps' activities and urinary excretion of natriuretic peptides.

BACKGROUND: In a previous study, we showed that a saponin mixture isolated from the roots of Ampelozizyphus amazonicus Ducke (SAPAaD) reduces urine excretion in rats that were given an oral loading of 0.9 % NaCl (4 ml/100 g body weight). In the present study, we investigated whether atrial natriuretic peptides (ANP) and renal ATPases play a role in the SAPAaD- induced antidiuresis in rats. METHODS: To evaluate the effect of SAPAaD on furosemide-induced diuresis, Wistar rats (250-300 g) were given an oral loading of physiological solution (0.9 % NaCl, 4 ml/100 g body weight) to impose a uniform water and salt state. The solution containing furosemide (Furo, 13 mg/kg) was given 30 min after rats were orally treated with 50 mg/kg SAPAaD (SAPAaD + Furo) or 0.5 ml of 0.9 % NaCl (NaCl + Furo). In the SAPAaD + NaCl group, rats were pretreated with SAPAaD and 30 min later they received the oral loading of physiological solution. Animals were individually housed in metabolic cages, and urine volume was measured every 30 min throughout the experiment (3 h). To investigate the role of ANP and renal Na(+) pumps on antidiuretic effects promoted by SAPAaD, rats were given the physiological solution (as above) containing SAPAaD (50 mg/kg). After 90 min, samples of urine and blood from the last 30 min were collected. Kidneys and atria were also removed after previous anesthesia. ANP was measured by radioimmunoassay (RIA) and renal cortical activities of Na(+)- and (Na(+),K(+))-ATPases were calculated from the difference between the [32P] Pi released in the absence and presence of 1 mM furosemide/2 mM ouabain and in the absence and presence of 1 mM ouabain, respectively. RESULTS: It was observed that SAPAaD inhibited furosemide-induced diuresis (at 90 min: from 10.0 ± 1.0 mL, NaCl + Furo group, n = 5, to 5.9 ± 1.0 mL, SAPAaD + Furo group n = 5, p < 0.05), increased both Na(+)-ATPase (from 25.0 ± 5.9 nmol Pi.mg(-1).min(-1), control, to 52.7 ± 8.9 nmol Pi.mg(-1).min(-1), p < 0.05) and (Na(+),K(+))-ATPase (from 47.8 ± 13.3 nmol Pi.mg(-1).min(-1), control, to 79.8 ± 6.9 nmol Pi .mg(-1).min(-1), p < 0.05) activities in the renal cortex. SAPAaD also lowered urine ANP (from 792 ± 132 pg/mL, control, to 299 ± 88 pg/mL, p < 0.01) and had no effect on plasma or atrial ANP. CONCLUSION: We concluded that the SAPAaD antidiuretic effect may be due to an increase in the renal activities of Na(+)- and (Na(+),K(+))-ATPases and/or a decrease in the renal ANP.

Sodio urinario como marcador bioquímico de la ingesta estimada de sal en niños y adolescentes / Urinary sodium as biochemical marker of estimated salt intake in children and adolescents / Sódio urinário como marcador bioquímico da ingestão de sal estimada em crianças e adolescentes

El objetivo de este trabajo fue estimar la ingesta de sal en niños y adolescentes "clínicamente sanos" utilizando como marcador o indicador bioquímico la excreción urinaria de sodio en 24 h. Se estudiaron 112 niños de ambos sexos, entre 5 y 15 años, sin restricción dietética, que concurrieron al Hospital de Pediatría - Posadas, Misiones. Se determinó la concentración de sodio en orina de 24 h utilizando un electrodo ión selectivo. La ingesta estimada de sal (g/día) se calculó a partir de: sodio urinario (mmol/día) x 58,5. No se encontraron diferencias significativas para la ingesta de sal por género. Los niños entre 9 y 15 años poseen una ingesta estimada (2,5 a 17 g sal/día) significativamente mayor (p < 0,05) que el grupo de 5 a 8 años (1,3 a 11,7 g sal/día). Un 24% de los niños de 5 a 8 años y sólo el 15% del grupo etáreo de 9 a 15 años, consumen de acuerdo a las recomendaciones establecidas por organismos internacionales. La ingesta de sal diaria estimada indica que un gran porcentaje de la población estudiada presenta una ingesta habitual elevada de sal, mayor a sus necesidades fisiológicas y a las metas recomendadas para prevenir la hipertensión arterial.

The aim of this study was to evaluate the estimated salt intake in "clinically healthy" children and adolescents, using the 24 h sodium urinary excretion as biochemical marker or indicator. A hundred and twelve male and female children aged 5 to 15, without a dietary restriction who visited the Province Pediatric Hospital - Posadas were evaluated. Urinary sodium in 24 hours was measured using the electrode selective ion method. The salt intake (g/day) was calculated as: urinary sodium (mmol/day) x 58.5. There were no significant differences in estimated salt intake by gender. Children aged from 9 to 15 have a significantly higher (p< 0.05) consumption (2.5 to 17 g salt /day) than those between the ages of 5 to 8 (1.3 a 11.7 g salt/day). A 24% of the children aged 5 to 8 and only a 15% at the age range 9 to 15 consume according international recommendations. The daily estimated salt intake indicates that a great percentage of the population studied presents a usual high consumption of salt, greater than their physiological needs and the recommended aims for prevention hypertension.

O objetivo deste trabalho foi estimar a ingestão de sal em crianças e adolescentes "clinicamente saudáveis" utilizando como marcador ou indicador bioquímico a excreção urinária de sódio em 24 h. Foram estudadas 112 crianças de ambos os sexos, entre 5 e 15 anos, sem restrição dietética, que assistiram ao Hospital de Pediatria - Posadas, Misiones. Determinou-se a concentração de sódio em urina de 24 h utilizando um eletrodo íon seletivo. A ingestão estimada de sal (g/dia) se calculou a partir do sódio urinário (mmoles/dia) x 58,5. Não se encontraram diferenças signiOcativas para a ingestão de sal por gênero. Crianças entre 9 e 15 anos têm uma ingestão estimada (2,5 a 17 g sal/dia) signiOcativamente maior (p < 0,05) que o grupo de 5 a 8 anos (1,3 a 11,7 g sal/dia). 24% das crianças de 5 a 8 anos e apenas 15% do grupo entre 9 e 15 anos, consomem conforme as recomendações estabelecidas por organismos internacionais. A ingestão de sal diária estimada indica que um grande percentual da população estudada apresenta ingestão habitual elevada de sal, maior a suas necessidades Osiológicas e às metas recomendadas para prevenir hipertensão arterial.

Effect of myricetin on deoxycorticosterone acetate (DOCA)-salt-hypertensive rats.

Chronic administration of myricetin (100 and 300 mg kg⁻¹, p.o., for 4 weeks) isolated from Vitis vinifera (Vitaceae) ameliorated hypertension and oxidative stress induced by deoxycorticosterone acetate (DOCA)-salt in rats. Myricetin treatment reduced systolic blood pressure, vascular reactivity changes and reversed the DOCA-induced increase in heart rate. Urinary sodium excretion was significantly decreased in animals treated with myricetin compared to the DOCA group when measured by flame photometer. The cumulative concentration response curve of serotonin (5-HT) and angiotensin II (Ang II) were shifted towards the right in rats treated with myricetin using the isolated rat fundus strip and ascending colon, respectively. Increased levels of thiobarbituric acid reactive substances and decreased levels of superoxide dismutase, catalase and reduced glutathione in the heart tissue were observed in animals treated with DOCA, which were reversed by myricetin. Thus, myricetin shows antihypertensive and antioxidant properties in the DOCA model of hypertension.

Lipopolysaccharide reduces sodium intake and sodium excretion in dehydrated rats.

The objective of this study was to find out if lipopolysaccharide (LPS) administered intraperitoneally affects sodium and water intake and renal excretion in dehydrated rats. LPS (0.3-5 mg/kg b.w.) inhibited 0.3M NaCl intake induced by subcutaneous injection of the diuretic furosemide (FURO, 10 mg/kg b.w.) combined with the angiotensin converting enzyme inhibitor, captopril (CAP, 5 mg/kg b.w.). Only the highest doses of LPS (2.5 and 5 mg/kg) inhibited water intake induced by FURO/CAP. LPS (0.6 mg/kg) reduced urinary volume and sodium excretion, but had no effect on mean arterial pressure or heart rate of rats treated with FURO/CAP. LPS (0.3-5.0 mg/kg) abolished intracellular thirst and reduced by 50% the urine sodium concentration of rats that received 2 ml of 2M NaCl by gavage. LPS (0.3-5.0 mg/kg) also reduced thirst in rats treated with FURO alone (10 mg/rat sc). The results suggest that LPS has a preferential, but not exclusive, inhibitory effect on sodium intake and on intracellular thirst. The inhibition of hydro-mineral intake and the antinatriuresis caused by LPS in dehydrated rats may contribute to the multiple effects of the endotoxin on fluid and electrolyte balance and be part of the strategy to cope with infections.

[Impaired gustatory sensitivity of the tongue to table salt as a risk factor of arterial hypertension].

The study included 630 patients with verified diagnosis of arterial hypertension (AH) in whom 24 hr AP monitoring was performed, threshold gustatory sensitivity of the tongue to table salt (TGS) measured, and habit to add salt to the cooked food evaluated. Measurement of Na in daily urine of 442 patients was followed by estimation of salt consumption. The results were compared with those obtained in 100 patients with newly diagnosed AH. The control group comprised 288 subjects. TGS in AH patients was significantly higher than in controls and directly related to clinical features of the disease, high AP values, age, smoking habits, hypercholesterolemia, abdominal-type obesity, and hereditary predisposition. TGS positively correlated with daily urinary excretion of NaCl (r = 0.4-0.7; p < 0.05-0.01). High TGS decreased under effect of hypotensive therapy.

Twelve-year trends and correlates of dietary salt intakes for the general adult population of Geneva, Switzerland.

BACKGROUND/OBJECTIVES: Investigate dietary salt intake trends by gender, and their associations with risk factors for cardiovascular diseases in Geneva, Switzerland. SUBJECTS/METHODS: Continuous surveillance of the Geneva general adult (35-74 years) population for 12 years (1993-2004) using a validated, semi-quantitative food frequency questionnaire (FFQ) in random, cross-sectional, representative samples (6688 men, 6647 women). Dietary salt intake assessment by FFQ excluded discretionary salt, but was calibrated on total salt intake using an independent validation substudy of 100 volunteers who additionally provided 24-h urine collections. RESULTS: Quartiles (mean) of calibrated dietary salt intake (g per day) were 9.9, 10.5, 11.2 (10.6) in men, and 7.0, 7.8, 8.9 (8.1) in women and were above current recommendations. Quartiles (mean) of salt density (g MJ(-1)) were 0.99, 1.16, 1.39 (1.23) in men, and 0.98, 1.12, 1.30 (1.17) in women. Both measures were stable during the 12-year surveillance period, regardless of hypertension treatment. Salt-density differences between cardiovascular disease risk factor subgroups were moderate. Salt density increased with age and body mass index. The main dietary non-discretionary salt food sources (men/women: 47/48%) were breads (17/17%), cheeses (11/10%), meat and meat products (8/7%), soups (6/9%) and ready-to-eat foods (5/5%). CONCLUSIONS: Salt intakes from all sources for the Geneva, and perhaps the Swiss adult population are above current recommendations. The quantitative and qualitative data provided in this paper could be used to develop and implement strategies for salt-intake reduction in Switzerland.

Albuminuria, intermittent hyperfiltration and salt wasting in patients with stroke: a pilot study.

OBJECTIVE: To investigate whether different types of stroke influence renal excretion of albumin, major electrolytes and water. MATERIAL AND METHODS: Timed urine collections were started shortly after admission in 5 patients with haemorrhagic stroke (group A), 5 with ischaemic stroke (group Bx), 6 with presumed ischaemic stroke (groups By/z) and 6 with subarachnoid haemorrhage (group C). Albuminuria was also investigated in four patients undergoing elective abdominal surgery. RESULTS: Increased levels of albuminuria were observed in all patients in groups A and B, but were found to decline with observation time and appeared to be related to outcome in group B. In group C, albuminuria was detected in 4 out of 6 patients. Elective surgery did not affect albumin excretion. In a setting with high urinary osmolality, high excretion rates for creatinine, urea, sodium, potassium and large diuresis were intermittently observed in groups A, B and C. None of these patients was in steady-state condition. CONCLUSIONS: Different types of stroke elicit a complex change in renal function which resembles the response to a hypervolaemic and hyperosmolar signal, possibly mediated by a breakdown of renal autoregulation of blood flow in the presence of high vasopressin activity. Acute changes in excretion of albumin might be an indicator of prognosis in stroke. The findings point to the existence of unrecognized pathways between the central nervous system and the kidneys. Further studies on the mechanisms underlying alterations in renal function in stroke and their implication for treatment and outcome are indicated.

Control of potassium excretion: a Paleolithic perspective.

PURPOSE OF REVIEW: Regulation of potassium (K) excretion was examined in an experimental setting that reflects the dietary conditions for humans in Paleolithic times (high, episodic intake of K with organic anions; low intake of NaCl), because this is when major control mechanisms were likely to have developed. RECENT FINDINGS: The major control of K secretion in this setting is to regulate the number of luminal K channels in the cortical collecting duct. Following a KCl load, the K concentration in the medullary interstitial compartment rose; the likely source of this medullary K was its absorption by the H/K-ATPase in the inner medullary collecting duct. As a result of the higher medullary K concentration, the absorption of Na and Cl was inhibited in the loop of Henle, and this led to an increased distal delivery of a sufficient quantity of Na to raise K excretion markedly, while avoiding a large natriuresis. In addition, because K in the diet was accompanied by 'future' bicarbonate, a role for bicarbonate in the control of K secretion via 'selecting' whether aldosterone would be a NaCl-conserving or a kaliuretic hormone is discussed. SUMMARY: This way of examining the control of K excretion provides new insights into clinical disorders with an abnormal plasma K concentration secondary to altered K excretion, and also into the pathophysiology of calcium-containing kidney stones.

Brain ouabain stimulates peripheral marinobufagenin via angiotensin II signalling in NaCl-loaded Dahl-S rats.

OBJECTIVE: In NaCl-loaded Dahl salt-sensitive (DS) rats the transient stimulation of brain endogenous ouabain (EO) precedes the increase in renal excretion of marinobufagenin (MBG), a vasoconstrictor and natriuretic. In hypertensive DS rats, EO raises blood pressure (BP) via an ATII-sensitive pathway. We hypothesized that an NaCl-induced increase in MBG is linked to the EO-stimulated ATII pathway. METHODS: We studied the effects of 3 h of NaCl loading (17 mmol/kg, intraperitoneally) in male DS rats treated with antibodies to MBG or ouabain, or with losartan (25 mg/kg). RESULTS: NaCl loading alone induced a transient stimulation of pituitary EO (22.4 +/- 1.8 versus 12.2 +/- 1.3 pmol/g) and ATII (39.4 +/- 2.8 versus 18.4 +/- 3.2 ng/g), a sustained increase in MBG excretion (5.2 +/- 0.6 versus 1.1 +/- 0.2 pmol/h), a 40% inhibition of the renal sodium pump, a natriuretic response, a 35 mmHg increase in systolic BP, and an increase in adrenocortical ATII and MBG levels and in plasma norepinephrine. The anti-MBG antibody reduced the natriuresis (36%) and BP (40 mmHg), and restored renal sodium pump activity. The anti-ouabain antibody prevented the increase in pituitary ATII, reduced MBG excretion, natriuresis and BP, increased sodium pump activity, and prevented increases in plasma norepinephrine, pituitary and adrenocortical ATII, and adrenocortical MBG. Losartan mimicked the effects of the anti-ouabain antibody, but did not affect the excretion of EO. In adrenocortical cells of DS rats, ATII stimulated MBG secretion, and losartan blocked this effect. CONCLUSIONS: In response to NaCl loading, brain EO, via an AT1 receptor pathway and probably via sympathetic activation, stimulates adrenocortical MBG, which inhibits the renal sodium pump and elevates BP.

Long-term compliance with salt restriction in Japanese hypertensive patients.

The purpose of the present study was to investigate the long-term compliance with salt restriction in Japanese hypertensive patients. Subjects included 389 patients, 230 women and 159 men, mean age 58+/-11 years, who underwent successful 24-h home urine collection more than three times over an interval of a year. Urinary salt, potassium, and creatinine were measured. Additionally, family history, habitual alcohol intake, smoking habit, physical activities, and job status were assessed by use of a questionnaire. During the follow-up period (average 3.5 years), participants underwent urine collection 4.6 times in average. Urinary salt excretion at the last visit was significantly lower than that at the first visit (8.7+/-3.4 vs. 9.6+/-4.1 g/day; p<0.01). Urinary potassium excretion also decreased significantly during this period (from 2.0+/-0.7 to 1.9+/-0.7 g/day; p<0.05). Among the mean 4.6 urine collections, 45.2% (men 34.6%, women 52.6%) of the patients successfully achieved <6 g (100 mmol of sodium)/day of salt excretion on at least one occasion. The rate of achievement of averaged urinary salt excretion <6 g/day dropped to 10.3% (men 4.4%, women 14.3%). Only 2.3% (men 0.6%, women 3.5%) of the patients achieved <6 g/day on all occasions. There were no significant differences in age, habitual alcohol intake, smoking habit, physical activities, or job status between patients who complied with the salt-restricted diet and those who did not. Results suggest that long-term compliance with salt restriction is poor in Japanese hypertensive patients. Since no specifically defining characteristics were found in the compliant patients, repeated measurements of urinary salt excretion seem to be important to encourage salt restriction.

Spinal anesthesia for arthroscopic knee surgery.

BACKGROUND AND OBJECTIVE: The purpose of the study was to compare the effects of adding 50 microg of morphine, 25 microg of fentanyl or saline to 6 mg of hyperbaric bupivacaine on postoperative analgesia and time to urination in patients undergoing arthroscopic knee surgery under spinal anesthesia. METHODS: The study was designed in a prospective, randomized, double-blinded and placebo-controlled manner. Sixty ASA I-II patients were randomized into the following three groups: Group BM: 6 mg of bupivacaine and 50 microg of morphine, Group BF: 6 mg of bupivacaine and 25 microg of fentanyl, and Group BS: 6 mg of bupivacaine and saline. Selective spinal anesthesia was performed in a lateral decubitus position, with the operative knee dependent for 10 min. RESULTS: In all groups satisfactory anesthesia was provided during the operation. There was a statistically significant difference between all the groups in times to voiding [Group BM 422 +/- 161 min; Group BF 244 +/- 163 min; Group BS 183 +/- 54 min (mean +/- SD)]. The incidence of pruritus was significantly greater in Group BM (80%) and BF (65%) in comparison with Group BS (no pruritus) (P < 0.05). The incidence of nausea was significantly increased in Group BM (35%) in comparison with Group BF (10%) and Group BS (P < 0.05). Analgesic consumption was significantly greater in Group BS in comparison with Groups BM and BF (P < 0.01). CONCLUSIONS: We conclude that during spinal anesthesia even mini-dose intrathecal morphine is not acceptable for outpatient surgery due to side-effects, especially severely prolonged time to urination.