Water Sodium Concentration Research Articles

Reducing drinking water sodium concentrations did not influence adolescent blood pressure

Abstract Previous investigations established that elementary and high school students residing in Reading, Massachusetts, displayed significantly higher blood pressure than their counterparts in the adjacent community of Stoneham, Massachusetts. Extensive evaluations of family history, dietary patterns, socio‐demographic variables and chemical measurements of drinking water revealed that the level of sodium in the drinking water was the variable most strongly associated with the higher blood pressure of the Reading students. A subsequent study, in which a group of Reading fifth graders’ families was given Stoneham water for all drinking and cooking purposes for a three month period., indicated that female but not male students displayed a significant decrease in their blood pressure. Subsequently, the Town of Reading announced its intention to reduce sodium levels in the drinking water by switching from the use of NaOH to CaOH as a pH adjustment technique. A study was set up to assess the impact of such a...

Renal Function in Freshwater and Chronically Saline-Stressed Male and Female Pekin Ducks

Hematocrit (Hct) and plasma ionic and osmotic concentrations were measured in Pekin Ducks, Anas platyrhynchos, drinking freshwater (FW), during rapid acclimation to sea water (RA), and after 6 mo exposure to 180-mM NaCl (SW). Glomerular filtration rate (GFR) and extracellular fluid volume (ECFV) were measured in FW and SW ducks. Estimated renal plasma flow (ERPF) was measured in SW ducks.During RA, Hct and plasma concentration increased significantly (P<.05) when drinking water sodium concentration ([Na]dw) was 300 mM; body mass decreased (P<.01) when [Na]dw was 375 mM. The Hct and plasma ionic or osmotic concentrations of FW and SW ducks were the same, except that female SW ducks had lower (P<.05) plasma chloride concentrations than FW female ducks. Relative to body mass, the FW female duck ECFV (26.88%) was larger (P<.01) than that of the male (17.50%). The ECFV was not affected by SW in either sex. Mean (± SE) GFR determined using inulin and polyethylene glycol (PEG) in the same five FW ducks, were the same, 4.4 ± .7 and 4.7 ± .6 mL(min kg)−1, respectively. In female FW ducks, the GFR (PEG) was 5.00 ± .30 mL(min kg)−1, significantly (P<.001) greater than that of the male, which was 3.07 ± .21 mL(min kg)−1. Female and male SW duck GFR were 3.96 ± .57 and 2.60 ± .37 mL(min kg)−1, respectively, but the decrease in GFR was significant (P<.05) only for females. The GFR were the same, relative to kidney mass, in both sexes. Male SW duck ERPF was 14.0 ± 1.9 mL (min kg)−1, not significantly different from the female SW duck ERPF, which was 17.2 ± 3.2 mL (min kg)−1. The ERPF was linearly related to the GFR (R2 = .78), with an apparent filtration fraction of 22% in both sexes.

Osmotic thirst suppression in dogs exposed to low ambient temperature

Body temperature, urine output, osmotic and free water clearances, plasma osmolality, sodium and potassium concentrations, blood lactate level, osmotic thirst and central blood volume were measured in dogs exposed to cold (+1 to −8°C) for 1–3 hours and compared to those obtained under control conditions at ambient temperatures (18–20°C). In some additional experiments osmotic thirst threshold and arterial blood pressure during intravenous infusion of norepinephrine were also examined. Exposure to low ambient temperature caused an increase in the osmotic thirst threshold and rise in central blood volume. Transient increase in the urine output and free water clearance accompained by a decrease in the urine osmolality were also observed. No changes were found in rectal temperature, plasma osmolality and plasma sodium concentration. Infusion of norepinephrine elevated the osmotic thirst threshold in a dose-dependent manner. It is concluded that the cold-induced suppression of osmotic thirst may result from the increased central blood volume. A possible involvement of the sympathetic nervous system in the thirst inhibition in low ambient temperature is also considered.

Investigation of auranofin-induced diarrhoea.

Gastrointestinal function was assessed in six patients with rheumatoid arthritis who had developed diarrhoea on treatment with Auranofin. With the administration of Auranofin whole gut transit time decreased markedly (to 50% or less of control values) in five of six patients. The speed of passage of intestinal contents through the colon was certainly increased but attempts to assess transit through the upper gastrointestinal tract failed because the breath hydrogen method gave inconclusive results. There was no evidence of colitis and in all cases biopsy of the rectal mucosa appeared normal by light microscopy. In the five patients with rapid intestinal transit faecal weight increased more than two-fold (range +44 to +335%) although in only three cases were the changes sufficient to cause an increased frequency of bowel action. Overall the concentration of sodium in faecal water increased three-fold (mean values rose from 10.6 to 38.3 mmol/l). There were no significant changes in the concentrations of either potassium or chloride but bicarbonate was reduced. Faecal pH fell from a mean value of 7.5 (range 6.8-7.9) to a mean value of 6.4 (range 6.0-7.4). In the three patients who developed overt diarrhoea and in two others taking Auranofin the intestinal uptake of 51Cr-EDTA was increased on average three-fold and there was a similar change in the ratio of the absorption of lactulose/mannitol. The mean clearance of alpha-1-antitrypsin from the circulation into the gastrointestinal tract was doubled. These data indicate an increase in intestinal permeability. In contrast the absorption of vitamin B12 was unaffected and there was no significant change in the excretion of faecal fat although one patient developed mild steatorrhoea. Thus in a selected group of subjects with rheumatoid arthritis the administration of Auranofin caused diarrhoea in association with a reversible defect in intestinal permeability but without significant change in the absorption of nutrients.

The lack of nephrotoxicity in the rat by sodium chlorite, a possible byproduct of chlorine dioxide disinfection in drinking water

Abstract This study evaluated the nephrotoxic effects of sodium chlorite when administered in the drinking water of male Sprague‐Dawley rats. Sodium chlorite was administered for periods of 30, 90, and 180 days and at concentrations of 31.2, 125, and 500 ppm (along with appropriate negative and positive controls). Examination of sections by light microscope revealed no abnormalities in the kidneys of the rats in the chlorite exposure groups. Water consumption, mortality, kidney weight, body weight change, and percent kidney to body weight ratio showed no statistically significant relationship to chlorite ion concentration, although an association was observed between the latter two parameters and sodium concentration of treatment water.

Sodium kinetics across dialysis membranes.

The kinetics of sodium across dialysis membranes were studied during diffusion and during convection utilizing cuprophan and cellulose hydrate membranes. During diffusion the changes in plasma water sodium concentration are correlated to the sodium concentration gradient between plasma water and dialysate but an increase also occurs when the gradient is annulled, due to the Donnan effect. During convection the plasma water sodium concentration increases during the passage through the dialyzer and the ultrafiltrate sodium concentration is significantly lower than the plasma water sodium concentration; this is due to the fact that the plasma proteins, as anions unable to cross the membrane, affect the kinetics of the sodium cations. Therefore, during diffusion the kinetics of sodium are mainly affected by the sodium concentration gradient and by the plasma protein concentration, while during convection the plasma protein concentration is the main factor affecting the kinetics of sodium.

Water Hardness and Urinary Stone Disease

On the macrogeographic scale, a strong negative association exists in the United States between water hardness and urinary stone disease. This investigation studies the association on the microgeographical scale, where it is possible to control for confounding environmental factors. The study was conducted on 2,295 patients from 2 regions: the Carolinas which had soft water and high stone incidence, and the Rockies which had hard water and low stone incidence. Home tap water samples from urinary stone patient hospitalizations were compared with that of controls, concurrent inguinal hernia patient hospitalization. After adjusting for environmental factors, no significant difference (p = 0.59) between the 2 groups was obtained in tap water calcium, magnesium, and sodium concentrations. An incidental but potentially important finding was that those consuming water from a private well had an estimated relative risk of 1.5 (p < 0.01) compared to those using public water. While no cause-effect relationship is suggested, stone-formers might consider avoiding private well water. On the other hand, water hardness should be a minor concern with respect to stone formation.

Protein and electrolyte alterations in human senile cataract

Water content, wet and dry weights of the crystalline lens, and protein, free amino acid and electrolyte levels in serum, aqueous humour and lens were determined in patients with nuclear senile cataract and at the different stages of the maturation of cortical cataract. In immature senile cortical cataract wet weight and sodium contents of the lens were significantly higher while potassium levels were low when compared with the nuclear cataract. With the maturation of cortical cataract water content, wet weight and sodium concentrations of the crystalline lens significantly increased while protein, free amino acid and potassium levels decreased. The possible role of these changes in various types of cataracts is discussed.

«Physiological» and «Pharmacological» Dialysate Sodium Concentrations

Forty three uremic patients on regular hemodialysis treatment (4 hours 3 times/week) were dialyzed for a period of 28.95 +/- 14.46 months with a dialysate sodium concentration (NaD) of 142 mEq/l, similar to their plasma water sodium concentration corrected for the Donnan factor ("physiological" NaD). Blood pressure (BP) and body weight (BW) dropped significantly. During two following periods, lasting 18 and 14 months, with NaD 148 mEq/l, similar to the patients' plasma water sodium concentration ("pharmacologically high" NaD), cardiovascular stability improved and BP did not show significant increase. Using "physiological" and "pharmacologically high" NaD the removal of water and sodium by convection improves the cardiovascular stability and the patients' well being, without bringing about the feared long-term cardiovascular side effects, if an appropriate dry body weight is achieved, because of better correction of the cellular overhydration.

Branchial Ionic Uptake and Acid-Base Regulation in the Rainbow Trout, Salmo Gairdneri

ABSTRACT Amiloride (10−4 M) inhibited sodium uptake in rainbow trout by 78% and was associated with a pronounced acidosis and decreases in both plasma total CO2* and [HCO3−]. 4-acetamiao-4′-iso-thiocyanatostilbene-2,2′disulphonicacid (SITS) (10−4 *m) in the bathing medium inhibited chloride uptake by 66% and following 6 h a significant decrease in plasma [H +] and significant increases in and [HCO3−] were observed. Inhibition of chloride uptake (50%) with external sodium bicarbonate (12 mm) resulted in a more rapid and pronounced alkalosis than did SITS inhibition. Hypercapnic acidosis had no significant effect on the rates of branchial sodium and chloride uptake. Increasing the concentration of sodium in the bathing water resulted in a less pronounced acidosis and a more rapid pH recovery during hypercapnia. These results are discussed with reference to the gill as an acid-base regulating structure. These findings are consistent with a gill model previously presented by Haswell, Randall &amp; Perry (1980).

The role of hydrostatic pressure in ischemic brain edema.

The mechanisms responsible for early prenecrotic ischemic brain edema were investigated in rats by comparing brain metabolism, tissue water (HOH) content, and sodium and potassium ion concentration in brain during ischemia induced by decapitation, by the Pulsinelli-Brierley technique, and by carotid embolization. Although brain metabolic functions were similarly disturbed in all three groups, an increase in brain HOH occurred only in the embolism model, which allowed collateral perfusion. Early ischemic brain edema is therefore dependent upon (1) impaired energy-dependent ion pumps and (2) a hydrostatic pressure gradient from patient vascular lumens. Elevated perfusion pressure increases the extent of this early edema. Induced hypertension causes impairment of blood-brain barrier function, as evidenced by extravasation of Evans blue dye 5 minutes after embolic ischemia, and strikingly increases the extent of macromolecular extravasation 4 hours after ictus. This increased protein leakage is accompanied by elevated HOH content and sodium concentration, as compared to findings in normotensive animals. It is concluded that the use of induced hypertension as a therapeutic modality in patients with acute stroke may be harmful.

Thirst and renal excretion of water and electrolytes during pyrogen fever in dogs.

Body temperature, water intake, urine output, sodium and potassium excretion, osmolal and free water clearance, plasma osmolality, sodium and potassium concentrations and osmotic thirst were examined in conscious dogs during pyrogen fever and compared to those found under control conditions. Arterial blood pressure and central venous pressure were also measured in some experiments. Administration of pyrogen produced transient but significant decreases in urine output and striking increases in the spontaneous water intake in some of the experiments in the phase of increasing fever. Arterial blood pressure decreased, whetreas central venous pressure increased at this stage of fever. No significant changes in renal excretion of solutes and free water as well as sodium and potassium were found. Plasma osmolality and sodium concentration increased and potassium concentration decreased unsignificantly both in control and pyrogen experiments. The main finding was that the thirst threshold to osmotic stimuli increased markedly during the phase of stabilized fever may be caused by significant increase in internal body temperature.

Faecal composition after surgery for Hirschsprung's disease.

Diarrhoea and perianal excoriation occur frequently after the endorectal pull-through operation for Hirschsprung's disease. A new method of faecal analysis was performed on 3-day stool collections in 17 postoperative Hirschsprung patients and in 14 normal children, in order to define the faecal abnormality and to establish the cause of perianal excoriation in these patients. Loose stools in postoperative patients were deficient in dry solid content and contained an excess of extractable faecal water. This also had a raised electrolyte concentration, particularly with respect to sodium. Total daily output of faecal water was normal. Formed stools from postoperative patients were also deficient in drysolids but had a normal extractable water content. Excess extractable faecal water, the main abnormality of loose stools in these patients, is the result of abnormal water absorption from the distal colon. Perianal excoriation in these patients is most closely associated with the concentration of sodium in faecal water.

Electrical, mechanical, and physical properties of denervated latissimus dorsi muscles of the chicken

The anterior (ALD) and posterior (PLD) latissimus dorsi muscles of Cornish-cross chickens were examined after 1 wk of denervation to determine changes which might occur in their electrical and mechanical properties. Both muscles exhibited increased percentage of water and intracellular sodium concentrations, and decreased intracellular potassium concentrations. Although the denervated PLD had a relative increase in the volume of its extracellular space, the ALD experienced a relative decrease in extracellular space. The normal resting membrane potential dropped from −70 mv (ALD) and −74 mv (PLD) to −57 mv after denervation. The mechanical threshold of the ALD, determined by potassium contracture studies, occurred at a lower [K] 0 in the denervated than in the control muscle; nevertheless, the resting potentials at threshold were the same. Similarly, the denervated ALD approached its maximum mechanical response at a lower [K] 0 than the control muscle, but at identical membrane potentials. This implies that the role of the membrane in excitation-contraction coupling was not eliminated by denervation. However, the denervated muscle developed only one-half the tension of the control muscle which suggests a deficiency in the excitation-contraction coupling process within the muscle fiber. The relationship between the resting potential and [K] 0 for the control ALD followed the Nernst equation, whereas potentials obtained from the denervated muscles were lower than predicted. This may be attributed to the effects of other ions on the resting potential, changes in the membrane permeability characteristics, or possible intracellular potassium binding.

Interrelations between total exchangeable sodium, potassium, body water, and serum sodium and potassium concentrations in hyponatremic and normonatremic heart disease.

Interrelations between total body water, total exchangeable cation (sodium + potassium), and cation (sodium + potassium) concentration of serum water were examined in 20 normonatremic and 11 hyponatremic edematous cardiac patients. The total exchangeable cation and total body water were highly significantly correlated in the normonatremic and hyponatremic groups. However, for the combined groups the correlation coefficient was lower than that found in the individual populations, and in covariance analysis the cation content in relation to total body water was significantly lower in the hyponatremic than in the normonatremic group. When it is assumed that the total exchangeable cation differs little from the total osmotically active cation, and that the cation concentrations of the extracellular and intracellular water are approximately equal, the ratio: total exchangeable cation ÷ cation concentration in serum water, that is, the cation space, should reflect the total body water. The cation space and total body water were highly significantly correlated in the normonatremic and hyponatremic groups, and the correlation coefficient remained at the same high level for the combined groups. The relationship between cation space and body water was very close to unity, and in covariance analysis no significant difference was found in cation space in relation to total body water. These results were confirmed in 10 sequential studies. It is concluded that the cation space in hyponatremic and normonatremic cardiac patients has proved to reflect the total body water very closely, and the implications of this finding are discussed.

Analysis of the Efflux Kinetics of Sodium from Small Cylinders of Rabbit Kidney Cortex

AbstractBojesen, E., P. P. Leyssac and B. S. Nielsen. Analysis of the efflux kinetics of sodium from small cylinders of rabbit kidney cortex. Acta physiol. scand. 1965. 65. 105–119. —Based upon two different two‐compartment models, a non‐communicating and a more realistic communicating two‐compartment system, the efflux curves from two cortical cylinders of rabbit kidney were sub‐ected to a graphical and a numerical analysis respectively. A fairly good correspondance was obtained between the results of both types of analysis and a surprisingly good fit with the experimental data was obtained by the numerical analysis. The results of the latter analysis showed that in the cylinders 85% and 80% of the exchangeable sodium was in diffusion equilibrium with the medium. The “diffusion coefficient” was calculated to be 7.3 × 10‐6 cm2 sec‐1 at 25°C and 13 × 10‐6 cm2. sec‐1 at 40°C. From separate determinations of the average concentration of exchangeable sodium in tissue water in a serie of cylinders of similar dimensions as those used for the analysis of the efflux curves, it was calculated that the fraction of exchangeable sodium, which is not in diffusion equilibrium with the medium (15–20 %), occupied a fraction of the tissue water of 30–45 % at a sodium concentration of about 55–40 meq/l. Taking an area to volume ratio corresponding to a single proximal tubule, a flux rate was calculated and found to be of an order of 10–100 times greater than that obtained in striated muscles by different investigators.

EFFECT OF EXPERIMENTAL CONGESTIVE HEART FAILURE AND ACETYL STROPHANTHIDIN ON MYOCARDIAL ELECTROLYTE AND WATER CONTENT.

The syndrome of chronic congestive heart failure was produced in female dogs by progressive pulmonary artery constriction. A factorial experimental design, containing seven experiments of four dogs each, was employed. Each experiment was completed in one day and consisted of two groups of two dogs each, one group containing dogs with heart failure and the other, normal dogs. One animal from each group received intravenous acetyl strophanthidin, 0.015 mg/kg ascites-free weight, while the other was given an injection of inert material. The heart was quickly removed from the chest nine minutes after the injection and the right ventricle was taken for analysis. Previous work indicated that this dose of the drug produced and inotropic effect both in normal animals and in dogs with heart failure without producing digitalis toxicity. The myocardium from animals with congestive heart failure contained significantly less potassium but more sodium, chloride, and water per kilogram of dry fat-free blood-free myocardium than the myocardium from normal dogs. The concentration of sodium plus potassium in tissue water was subnormal in failing hearts. The sodium and chloride composition of the fluid gained by failing hearts differed significantly from that of interstitial fluid. Acetyl strophanthidin increased myocardial chloride and water. Although potassium in the myocardium was unchanged in treated control dogs, it increased significantly after acetyl strophanthidin in animals with heart failure. The findings are consistent with myocardial cellular swelling in congestive heart failure. The quantity of blood in each kilogram of failing myocardial tissue was severely reduced, probably because of muscle fiber hypertrophy. The possibility is considered that this alteration, together with the increased tissue water, may lead to lowered oxygen tension in failing heart muscle. It is suggested that digitalis exerts two opposing effects on ion transport through the myocardial cell membrane and that neither of these is fundamental to its inotropic action.

Abnormalities of body water, sodium, potassium, and magnesium; pathogenesis, clinical manifestations, and treatment.

I. CLASSIFICATION The classification of abnormalities of water volume and/or sodium concentration is presented in Table 1. 1 From the standpoint of pathogenesis, the abnormalities may be di- vided into two groups: ( a ) conditions characterized by a primary alteration in extracellular volume or sodium concentration and a secondary shift of water between interstitial tissue and cells to effect equilibrium of osmotic pressure;* ( b ) conditions characterized by a primary cellular disturbance, with alteration in the content or concentration of osmotically active intracellular electrolytes and a parallel change in the osmolarity of the extracellular compartment. The pathogenesis and clinical manifestations of these two groups are presented separately. II. PATHOGENESIS OF PRIMARY ABNORMALITIES Pathogenesis of primary abnormalities of water volume and sodium concentration is given in Table 2.† The basic predisposing factor in the dehydration syndrome is fluid loss.‡ If losses continue unchecked, the syndrome likely to develop will depend partly upon the