1. The electrolyte and water composition of urine and ileal fluid was studied in six patients with ileostomies during dietary sodium deprivation and at the same time measurements were made of plasma renin activity, plasma aldosterone concentration, renal aldosterone excretion and plasma arginine vasopressin concentration. 2. In each subject there was a reduction in renal sodium excretion within...

Occasionally measurement of the serumn or plasma concentration of sodium may give rise to falsely low results when carried out on a flame photometer or by an indirect reading ion selective electrode. The patients at risk are those with abnormally high serum concentrations of lipid or protein. These are, however, few: initially all low sodium concentrations as measured by flame photometry should...

Older literature has suggested that the plasma sodium concentration is not individual, that it is neither intrinsic to an individual nor reproducible, longitudinally. We recently observed that the plasma sodium concentration is heritable. Because demonstrable heritability requires individuality of the relevant phenotype, we hypothesized that the plasma sodium concentration was substantially ind...

1. The role of the plasma sodium concentration in the regulation of aldosterone secretion and sodium excretion was investigated by comparing in 13 conscious sodium-depleted dogs the effects of the same sodium load (2.5 mmol/kg) given as either a hypertonic or hypotonic infusion. 2. The plasma sodium concentration was significantly higher and the plasma aldosterone concentration and urinary aldo...

The stationary intracellular potassium concentration in E. coli B 525 has been studied as a function of the extracellular potassium and sodium concentrations. The ratio of extracellular to intracellular potassium concentration is shown to be a linear function of the extracellular potassium concentration if the extracellular sodium concentration is low (20 mmoles/1). In the case of high sodium c...

Plasma aldosterone concentration can increase in anephric man during hemodialysis despite the lack of kidneys to produce renin. Because the metabolic clearance rate of aldosterone does not change during hemodialysis, aldosterone secretion must increase in response to sodium depletion, volume depletion, or both. This study was designed to determine the relative influence of sodium and volume dep...