Potassium Imbalance and Phosphate Renal Handling: A Micropuncture Study
In order to study the relationship between potassium excretion and that of the main urinary buffer, i.e. phosphate, rat micropuncture experiments were carried out. The effects of acute potassium loading and chronic potassium depletion on phosphate transport along superficial nephrons were evaluated: marked antiphosphaturia was observed in both conditions. Whereas an impaired renal response to parathyroid hormone (PTH) in potassium depletion had already been described (1) it was not known whether such a mechanism might be involved in acute hyperkalemia. Hence, in an additional series of clearance experiments during acute hyperkalemia, the effect of parathyroidectomy on the potassium-induced reduction of phosphate excretion was also assessed.
KeywordsDistal Tubule Phosphate Transport Phosphate Excretion Renal Phosphate Tubular Fluid
Unable to display preview. Download preview PDF.
- 2.B. Karlmark, Ph. Jaeger, and G. Giebisch. Luminal buffer transport in the rat cortical tubule: relationship to potassium metabolism. Am. J. Physiol. (submitted).Google Scholar
- 3.B. Karlmark, Ph. Jaeger, H. Fein, and G. Giebisch. Coulometric acid-base titration in nanoliter samples with glass and antimony electrodes. Am. J. Physiol. (in press).Google Scholar
- 4.Ph. Jaeger, B. Karlmark, B. Stanton, R.G. Kirk, and G. Giebisch. Micropuncture study of distal tubular activation of phosphate reabsorption in the rat. Advances in Exp. Med. and Biol. 128: 77 (1980). Phosphate and minerals in health and disease. S.G. Massry, E. Ritz and H. Jahn, editors.Google Scholar