Abstract
The ability of the kidney to reabsorb bicarbonate is held to be a function of plasma CO2 tension, carbonic anhydrase activity, and potassium stores. The effects of alterations of extracellular volume on bicarbonate reabsorption were studied in dogs whose arterial Pco2 was kept constant at 40 mm Hg (range 35-45 mm Hg).
The effect of extracellular volume expansion was studied in dogs receiving hypertonic bicarbonate and isotonic saline, isotonic saline alone (two of the animals in this group received HCl to lower the plasma bicarbonate concentration), and isotonic bicarbonate. The results were similar in each group. Extracellular volume expansion depressed bicarbonate reabsorption. This depression was related not to changes in glomerular filtration rate (GFR) or bicarbonate concentration, but to the increase of fractional sodium excretion. In addition, volume expansion with bicarbonate increased chloride excretion.
Bicarbonate loading was performed in two groups of dogs in which effective expansion of extracellular volume was minimized by hemorrhage or acute constriction of the thoracic vena cava. Both groups demonstrated enhanced bicarbonate reabsorption relative to that seen in the volume-expanded groups. Release of the caval ligature promptly decreased bicarbonate reabsorption.
Plasma potassium decreased in all animals studied, but the changes in bicarbonate reabsorption noted could not be related to the decrease.
This study demonstrates that the state of effective extracellular volume is a major determinant of bicarbonate reabsorption by the kidney.
Full text
PDF









Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Cirksena W. J., Dirks J. H., Berliner R. W. Effect of thoracic cava obstruction on response of proximal tubule sodium reabsorption to saline infusion. J Clin Invest. 1966 Feb;45(2):179–186. doi: 10.1172/JCI105330. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cohen J. J. Correction of metabolic alkalosis by the kidney after isomertric expansion of extracellular fluid. J Clin Invest. 1968 May;47(5):1181–1192. doi: 10.1172/JCI105807. [DOI] [PMC free article] [PubMed] [Google Scholar]
- DE WARDENER H. E., MILLS I. H., CLAPHAM W. F., HAYTER C. J. Studies on the efferent mechanism of the sodium diuresis which follows the administration of intravenous saline in the dog. Clin Sci. 1961 Oct;21:249–258. [PubMed] [Google Scholar]
- GULYASSY P. F., VAN YPERSELE DE STRIHOU C., SCHWARTZ W. B. On the mechanism of nitrate-induced alkalosis. The possible role of selective chloride depletion in acid-base regulation. J Clin Invest. 1962 Oct;41:1850–1862. doi: 10.1172/JCI104642. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gilmore J. P., Michaelis L. L. Influence of anesthesia on renal responses of the foxhound to intravascular volume expansion. Am J Physiol. 1969 Jun;216(6):1367–1369. doi: 10.1152/ajplegacy.1969.216.6.1367. [DOI] [PubMed] [Google Scholar]
- HILTON J. G., CAPECI N. E., KISS G. T., KRUESI O. R., GLAVIANO V. V., WEGRIA R. The effect of acute elevation of the plasma chloride concentration on the renal excretion of bicarbonate during acute respiratory acidosis. J Clin Invest. 1956 May;35(5):481–487. doi: 10.1172/JCI103300. [DOI] [PMC free article] [PubMed] [Google Scholar]
- KASSIRER J. P., BERKMAN P. M., LAWRENZ D. R., SCHWARTZ W. B. THE CRITICAL ROLE OF CHLORIDE IN THE CORRECTION OF HYPOKALEMIC ALKALOSIS IN MAN. Am J Med. 1965 Feb;38:172–189. doi: 10.1016/0002-9343(65)90172-5. [DOI] [PubMed] [Google Scholar]
- Kassirer J. P., Schwartz W. B. Correction of metabolic alkalosis in man without repair of potassium deficiency. A re-evaluation of the role of potassium. Am J Med. 1966 Jan;40(1):19–26. doi: 10.1016/0002-9343(66)90183-5. [DOI] [PubMed] [Google Scholar]
- LEVINSKY N. G., LALONE R. C. SODIUM EXCRETION DURING ACUTE SALINE LOADING IN DOGS WITH VENA CAVAL CONSTRICTION. J Clin Invest. 1965 Apr;44:565–573. doi: 10.1172/JCI105169. [DOI] [PMC free article] [PubMed] [Google Scholar]
- LEVINSKY N. G., LALONE R. C. THE MECHANISM OF SODIUM DURESIS AFTER SALINE INFUSION IN THE DOG. J Clin Invest. 1963 Aug;42:1261–1276. doi: 10.1172/JCI104811. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Levinsky N. G. Nonaldosterone influences on renal sodium transport. Ann N Y Acad Sci. 1966 Nov 22;139(2):295–303. doi: 10.1111/j.1749-6632.1966.tb41204.x. [DOI] [PubMed] [Google Scholar]
- NEEDLE M. A., KALOYANIDES G. J., SCHWARTZ W. B. THE EFFECTS OF SELECTIVE DEPLETION OF HYDROCHLORIC ACID ON ACID-BASE AND ELECTROLYTE EQUILIBRIUM. J Clin Invest. 1964 Sep;43:1836–1846. doi: 10.1172/JCI105057. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Purkerson M. L., Lubowitz H., White R. W., Bricker N. S. On the influence of extracellular fluid volume expansion on bicarbonate reabsorption in the rat. J Clin Invest. 1969 Sep;48(9):1754–1760. doi: 10.1172/JCI106141. [DOI] [PMC free article] [PubMed] [Google Scholar]
- RECTOR F. C., Jr, VANGIESEN G., KIIL F., SELDIN D. W. INFLUENCE OF EXPANSION OF EXTRACELLULAR VOLUME ON TUBULAR REABSORPTION OF SODIUM INDEPENDENT OF CHANGES IN GLOMERULAR FILTRATION RATE AND ALDOSTERONE ACTIVITY. J Clin Invest. 1964 Mar;43:341–348. doi: 10.1172/JCI104919. [DOI] [PMC free article] [PubMed] [Google Scholar]