Abstract
We studied two groups of rats acutely loaded with bicarbonate, control rats on a standard diet and rats kept on a K-free diet for 3 wk. Compared with controls, K-depleted rats had reduced fractional excretion of bicarbonate despite their elevated filtered bicarbonate load. Distal bicarbonate reabsorption increased in K-depleted rats. In the presence of almost identical early distal bicarbonate loads (481 +/- 40 pmol/min in controls and 444 +/- 50 pmol/min in K depletion), distal bicarbonate reabsorption was significantly enhanced in K depletion (247 +/- 17 pmol/min) as compared with controls (179 +/- 18 pmol/min). These values are significantly different from each other, and both are severalfold higher than bicarbonate reabsorption in nonloaded conditions. In conclusion, distal bicarbonate reabsorption is load dependent, and distal bicarbonate reabsorption is stimulated in K depletion.
Full text
PDF





Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Alpern R. J., Cogan M. G., Rector F. C., Jr Effect of luminal bicarbonate concentration on proximal acidification in the rat. Am J Physiol. 1982 Jul;243(1):F53–F59. doi: 10.1152/ajprenal.1982.243.1.F53. [DOI] [PubMed] [Google Scholar]
- Alpern R. J. Mechanism of basolateral membrane H+/OH-/HCO-3 transport in the rat proximal convoluted tubule. A sodium-coupled electrogenic process. J Gen Physiol. 1985 Nov;86(5):613–636. doi: 10.1085/jgp.86.5.613. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Aronson P. S. Mechanisms of active H+ secretion in the proximal tubule. Am J Physiol. 1983 Dec;245(6):F647–F659. doi: 10.1152/ajprenal.1983.245.6.F647. [DOI] [PubMed] [Google Scholar]
- Aronson P. S., Nee J., Suhm M. A. Modifier role of internal H+ in activating the Na+-H+ exchanger in renal microvillus membrane vesicles. Nature. 1982 Sep 9;299(5879):161–163. doi: 10.1038/299161a0. [DOI] [PubMed] [Google Scholar]
- Boron W. F., Boulpaep E. L. Intracellular pH regulation in the renal proximal tubule of the salamander. Basolateral HCO3- transport. J Gen Physiol. 1983 Jan;81(1):53–94. doi: 10.1085/jgp.81.1.53. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Brisolla-Diuana A., Amorena C., Malnic G. Transfer of base across the basolateral membrane of cortical tubules of rat kidney. Pflugers Arch. 1985 Oct;405(3):209–215. doi: 10.1007/BF00582562. [DOI] [PubMed] [Google Scholar]
- Burckhardt B. C., Sato K., Frömter E. Electrophysiological analysis of bicarbonate permeation across the peritubular cell membrane of rat kidney proximal tubule. I. Basic observations. Pflugers Arch. 1984 May;401(1):34–42. doi: 10.1007/BF00581530. [DOI] [PubMed] [Google Scholar]
- Capasso G., Kinne R., Malnic G., Giebisch G. Renal bicarbonate reabsorption in the rat. I. Effects of hypokalemia and carbonic anhydrase. J Clin Invest. 1986 Dec;78(6):1558–1567. doi: 10.1172/JCI112748. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cemerikić D., Wilcox C. S., Giebisch G. Intracellular potential and K+ activity in rat kidney proximal tubular cells in acidosis and K+ depletion. J Membr Biol. 1982;69(2):159–165. doi: 10.1007/BF01872275. [DOI] [PubMed] [Google Scholar]
- Chan Y. L., Biagi B., Giebisch G. Control mechanisms of bicarbonate transport across the rat proximal convoluted tubule. Am J Physiol. 1982 May;242(5):F532–F543. doi: 10.1152/ajprenal.1982.242.5.F532. [DOI] [PubMed] [Google Scholar]
- Cogan M. G., Maddox D. A., Lucci M. S., Rector F. C., Jr Control of proximal bicarbonate reabsorption in normal and acidotic rats. J Clin Invest. 1979 Nov;64(5):1168–1180. doi: 10.1172/JCI109570. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cohen L. HCO3-Cl exchange transport in the adaptive response to alkalosis by turtle bladder. Am J Physiol. 1980 Aug;239(2):F167–F174. doi: 10.1152/ajprenal.1980.239.2.F167. [DOI] [PubMed] [Google Scholar]
- DuBose T. D., Jr, Pucacco L. R., Lucci M. S., Carter N. W. Micropuncture determination of pH, PCO2, and total CO2 concentration in accessible structures of the rat renal cortex. J Clin Invest. 1979 Aug;64(2):476–482. doi: 10.1172/JCI109485. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Giebisch G., Malnic G., De Mello G. B., De Mello Aires M. Kinetics of luminal acidification in cortical tubules of the rat kidney. J Physiol. 1977 Jun;267(3):571–599. doi: 10.1113/jphysiol.1977.sp011827. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Good D. W. Sodium-dependent bicarbonate absorption by cortical thick ascending limb of rat kidney. Am J Physiol. 1985 Jun;248(6 Pt 2):F821–F829. doi: 10.1152/ajprenal.1985.248.6.F821. [DOI] [PubMed] [Google Scholar]
- Jacobson H. R. Medullary collecting duct acidification. Effects of potassium, HCO3 concentration, and pCO2. J Clin Invest. 1984 Dec;74(6):2107–2114. doi: 10.1172/JCI111635. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jacobson H. R., Seldin D. W. On the generation, maintenance, and correction of metabolic alkalosis. Am J Physiol. 1983 Oct;245(4):F425–F432. doi: 10.1152/ajprenal.1983.245.4.F425. [DOI] [PubMed] [Google Scholar]
- Koeppen B. M., Helman S. I. Acidification of luminal fluid by the rabbit cortical collecting tubule perfused in vitro. Am J Physiol. 1982 May;242(5):F521–F531. doi: 10.1152/ajprenal.1982.242.5.F521. [DOI] [PubMed] [Google Scholar]
- Kunau R. T., Jr, Walker K. A. Total CO2 absorption in the distal tubule of the rat. Am J Physiol. 1987 Mar;252(3 Pt 2):F468–F473. doi: 10.1152/ajprenal.1987.252.3.F468. [DOI] [PubMed] [Google Scholar]
- Laski M. E., Kurtzman N. A. Characterization of acidification in the cortical and medullary collecting tubule of the rabbit. J Clin Invest. 1983 Dec;72(6):2050–2059. doi: 10.1172/JCI111170. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Levine D. Z. An in vivo microperfusion study of distal tubule bicarbonate reabsorption in normal and ammonium chloride rats. J Clin Invest. 1985 Feb;75(2):588–595. doi: 10.1172/JCI111735. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lucci M. S., Pucacco L. R., DuBose T. D., Jr, Kokko J. P., Carter N. W. Direct evaluation of acidification by rat proximal tubule: role of carbonic anhydrase. Am J Physiol. 1980 May;238(5):F372–F379. doi: 10.1152/ajprenal.1980.238.5.F372. [DOI] [PubMed] [Google Scholar]
- Luke R. G., Galla J. H. Chloride-depletion alkalosis with a normal extracellular fluid volume. Am J Physiol. 1983 Oct;245(4):F419–F424. doi: 10.1152/ajprenal.1983.245.4.F419. [DOI] [PubMed] [Google Scholar]
- Maddox D. A., Gennari F. J. Load dependence of HCO3 and H2O reabsorption in the early proximal tubule of the Munich-Wistar rat. Am J Physiol. 1985 Jan;248(1 Pt 2):F113–F121. doi: 10.1152/ajprenal.1985.248.1.F113. [DOI] [PubMed] [Google Scholar]
- Malnic G., De Mello Aires M., Giebisch G. Micropuncture study of renal tubular hydrogen ion transport in the rat. Am J Physiol. 1972 Jan;222(1):147–158. doi: 10.1152/ajplegacy.1972.222.1.147. [DOI] [PubMed] [Google Scholar]
- Malnic G., de Mello-Aires M. Kinetic study of bicarbonate reabsorption in proximal tubule of the rat. Am J Physiol. 1971 Jun;220(6):1759–1767. doi: 10.1152/ajplegacy.1971.220.6.1759. [DOI] [PubMed] [Google Scholar]
- McKinney T. D., Burg M. B. Bicarbonate absorption by rabbit cortical collecting tubules in vitro. Am J Physiol. 1978 Feb;234(2):F141–F145. doi: 10.1152/ajprenal.1978.234.2.F141. [DOI] [PubMed] [Google Scholar]
- Murer H., Hopfer U., Kinne R. Sodium/proton antiport in brush-border-membrane vesicles isolated from rat small intestine and kidney. Biochem J. 1976 Mar 15;154(3):597–604. [PMC free article] [PubMed] [Google Scholar]
- Oberleithner H. Intracellular pH in diluting segment of frog kidney. Pflugers Arch. 1985 Jul;404(3):244–251. doi: 10.1007/BF00581246. [DOI] [PubMed] [Google Scholar]
- Sabatini S. Effect of cyclic AMP on acidification in the isolated turtle bladder. Kidney Int. 1985 Jan;27(1):25–30. doi: 10.1038/ki.1985.5. [DOI] [PubMed] [Google Scholar]
- Sasaki S., Berry C. A., Rector F. C., Jr Effect of luminal and peritubular HCO3(-) concentrations and PCO2 on HCO3(-) reabsorption in rabbit proximal convoluted tubules perfused in vitro. J Clin Invest. 1982 Sep;70(3):639–649. doi: 10.1172/JCI110658. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stone D. K., Seldin D. W., Kokko J. P., Jacobson H. R. Anion dependence of rabbit medullary collecting duct acidification. J Clin Invest. 1983 May;71(5):1505–1508. doi: 10.1172/JCI110905. [DOI] [PMC free article] [PubMed] [Google Scholar]