Increase In Chloride Excretion Research Articles

Kaliuresis in Normal Subjects following Oral Potassium Citrate Intake without Increased Plasma Potassium Concentration

Ingestion of potassium salts typically induces both a kaliuresis and an increase in the systemic plasma potassium concentration. In this study normal healthy adults undergoing water diuresis ingested potassium citrate or sodium citrate (0.5 mmol/kg body weight) or continued without ion ingestion (a time control group). Urine was collected over 20-min intervals and venous blood sampled at midinterval. Intake of potassium citrate led to a significant increase in potassium excretion that began during the first postingestion collection and peaked 60-80 min after intake with a maximal increase in potassium excretion above baseline of 1.60 mumol/min.kg-1. The kaliuresis occurred without changes in plasma potassium concentration, excretion of creatinine or calcium, or urine hypo-osmolality and was associated with a briefer, smaller, and less regular increase in sodium excretion and a pronounced but irregular increase in chloride excretion. Plasma aldosterone was insignificantly elevated above baseline, and the initial increase did not occur until 40-60 min after potassium intake. Intake of sodium citrate did not produce a kaliuresis. The cause of the kaliuresis does not appear to be an increased systemic plasma potassium concentration, an increased plasma level of aldosterone, intake of citrate, or an elevated excretion of sodium. The mechanism inducing the kaliuresis following oral potassium intake in the absence of changes in systemic plasma potassium may involve a reflex initiated at potassium sensors in gut, portal vein, or liver.

The role of potassium in the control of ammonium excretion during starvation

Administration of KC1 0.5 mmol/kg/day to subjects undergoing prolonged starvation reduced daily urimary ammonium and β-hydroxybutyrate excretion by one-third. These changes were accompanied by an improvement in potassium balance and an increased rate of chloride excretion. A similar fall in ammonium excretion occurred in a second group of subjects after administration of KHCO 3 0.5 mmol/kg/day. Ketone body and bicarbonate excretion remained unchanged in this group while potassium balance improved. In both the first and second groups urine pH fell significantly as the rate of excretion of urinary buffer (ammonium) decreased. When the dose of KHCO 3 was increased to 1.5–2.0 mmol/kg/day in fasting subjects, the urine was alkalinized, and ammonium excretion fell to negligible levels, resulting in nitrogen sparing of 2.0 g/day. The results indicate that one-half of the increase in ammonium excretion observed in starvation is due to potassium deficiency. Nitrogen wastage caused by losses of urinary ammonium during starvation can be virtually eliminated by potassium supplementation and urinary alkalinization. The decrease in β-hydroxybutyrate excretion after potassium chloride administration was not caused by a fall in the rate of nonionic diffusion of this organic acid related to the reduction in urine pH. The reason for the fall in β-hydroxybutyrate excretion is not apparent, though it was associated with an increase in chloride excretion.

Effect of "Furosemid" on chloride and water excretion in single nephrons of the kidney of the rat.

IT has been shown by Muschaweck and Hajdu1 that in the dog, at doses of 10 mg/kg body-wt. and more, ‘Furosemid’ (4-chloro-N(2-furylmethyl)-5-sulphamoyl-anthranylic acid) markedly increases the excretion of water, sodium and chloride. These authors also showed that the increase in chloride excretion was proportionally greater than that of sodium and water. On the other hand, Karger and Nagel2 found a reduced permeability to anions, especially chloride, in the frog skin after addition of ‘Furosemid’ at concentrations of 25–500 mg/1. to the bathing solution, as evidenced by increased transmembrane potential differences without change in the short circuit current. Deetjen3 obtained proximal and distal tubular fluid samples in rats with an intravenous infusion of 2 mg/kg/min and observed significantly decreased proximal fluid/plasma (F/P) inulin ratios, as well as ratios below 2 in the distal tubule, concluding that ‘Furosemid’ depresses water and salt re-absorption in the proximal tubule and ascending limb of Henle's loop. Clearance studies by Suki, Rector and Seldin4 also indicated that ‘Furosemid’ might have an effect on the activity of the re-absorptive mechanisms of the proximal tubule and the ascending limb of Henle's loop.

Effect of a Mercurial Diuretic on Thyroid Uptake and Renal Clearance of Radioiodine.

Summary1. Meralluride sodium (Mercuhydrin®) had no effect upon the results ol the 6 and 24 hour ithyroid uptake procedure in 8 euthyroid patients. 2. Renal I131 clearances were determined before and after injection of meralluride sodium in 4 patients, and compared with simultaneous chloride excretion data. Radioiodide clearances remained unchanged in the face of a consistent and marked increase in chloride excretion.