Skip to main content
The Journal of Clinical Investigation logoLink to The Journal of Clinical Investigation
. 1974 Nov;54(5):1040–1048. doi: 10.1172/JCI107847

A Microperfusion Study of Phsophate Reabsorption by the Rat Proximal Renal Tubule EFFECT OF PARATHYROID HORMONE

Norman Bank 1,2, Hagop S Aynedjian 1,2, Stephen W Weinstein 1,2
PMCID: PMC301651  PMID: 4418449

Abstract

To study the mechanism of phsophate reabsorption by the proximal tubule and the effect of parathyroid hormone (PTH), microperfusion experiments were carried out in rats. Segments of proximal tubule isolated by oil blocks were perfused in vivo with one of three solutions, each containing 152 meq/liter Na+ and 2 mmol/liter phosphate, but otherwise differing in composition. The pH of solution 1 was 6.05-6.63, indicating that 60-85% of the phosphate was in the form of H2PO4-. The pH of solution 2 was 7.56-7.85, and 85-92% of the phosphate was in the form of HPO4=. Solution 3 contained HCO3- and glucose and had a pH of 7.50-7.65. When the proximal tubules were perfused with solution 1, the 32P concentration in the collected perfusate was found to be consistently lower than in the initial perfusion solution. In sharp contrast, when the tubules were perfused with solutions 2 or 3, 32P concentration usually rose above that in the initial solution. Water (and persumably Na+) reabsorption, as measured with [3H]inulin, was the same with the acid and alkaline solutions. Administration of partially purified PTH clearly prevented the fall in phosphate concentration with the acid solution, but had a less discernible effect on phosphate reabsorption with the two alkaline solutions. Measurements of pH within the perfused segments with antimony microelectrodes demonstrated that PTH enhanced alkalinization of the acid perfusion solution. The findings are consistent with the view that H2PO4- is reabsorbed preferentially over HPO4=. This can be attributed to either an active transport mechanism for H2PO4- or selective membrane permeability to this anion. PTH appears to either inhibit an active transport process for H2PO4-, or to interfere with passive diffusion of phosphate by alkalinizing the tubular lumen.

Full text

PDF

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Agus Z. S., Gardner L. B., Beck L. H., Goldberg M. Effects of parathyroid hormone on renal tubular reabsorption of calcium, sodium, and phosphate. Am J Physiol. 1973 May;224(5):1143–1148. doi: 10.1152/ajplegacy.1973.224.5.1143. [DOI] [PubMed] [Google Scholar]
  2. Agus Z. S., Puschett J. B., Senesky D., Goldberg M. Mode of action of parathyroid hormone and cyclic adenosine 3',5'-monophosphate on renal tubular phosphate reabsorption in the dog. J Clin Invest. 1971 Mar;50(3):617–626. doi: 10.1172/JCI106532. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Amiel C., Kuntziger H., Richet G. Micropuncture study of handling of phosphate by proximal and distal nephron in normal and parathyroidectomized rat. Evidence for distal reabsorption. Pflugers Arch. 1970;317(2):93–109. doi: 10.1007/BF00592495. [DOI] [PubMed] [Google Scholar]
  4. BANK N. Relationship between electrical and hydrogen ion gradients across rat proximal tubule. Am J Physiol. 1962 Sep;203:577–582. doi: 10.1152/ajplegacy.1962.203.3.577. [DOI] [PubMed] [Google Scholar]
  5. Bank N., Aynedjian H. S. A microperfusion study of bicarbonate accumulation in the proximal tubule of the rat kidney. J Clin Invest. 1967 Jan;46(1):95–102. doi: 10.1172/JCI105515. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Bank N., Aynedjian H. S. A micropuncture study of potassium excretion by the remnant kidney. J Clin Invest. 1973 Jun;52(6):1480–1490. doi: 10.1172/JCI107322. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Bank N., Aynedjian H. S. Techniques of microperfusion of renal tubules and capillaries. Yale J Biol Med. 1972 Jun-Aug;45(3-4):312–317. [PMC free article] [PubMed] [Google Scholar]
  8. Bank N., Yarger W. E., Aynedjian H. S. A microperfusion study of sucrose movement across the rat proximal tubule during renal vein constriction. J Clin Invest. 1971 Feb;50(2):294–302. doi: 10.1172/JCI106494. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Barratt L. J., Rector F. C., Jr, Kokko J. P., Seldin D. W. Factors governing the transepithelial potential difference across the proximal tubule of the rat kidney. J Clin Invest. 1974 Feb;53(2):454–464. doi: 10.1172/JCI107579. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Beck L. H., Goldberg M. Effects of acetazolamide and parathyroidectomy on renal transport of sodium, calcium, and phosphate. Am J Physiol. 1973 May;224(5):1136–1142. doi: 10.1152/ajplegacy.1973.224.5.1136. [DOI] [PubMed] [Google Scholar]
  11. CARRASQUER G., BRODSKY W. A. Eliminatio of transient secretion of phosphate by alkalinization of plasma in dogs. Am J Physiol. 1961 Sep;201:499–504. doi: 10.1152/ajplegacy.1961.201.3.499. [DOI] [PubMed] [Google Scholar]
  12. Frick A. Mechanism of inorganic phosphate diuresis secondary to saline infusions in the rat. Excretion of sodium, inorganic phosphate, and calcium in normal and in parathyroidectomized rats. Pflugers Arch. 1969;313(2):106–122. doi: 10.1007/BF00586239. [DOI] [PubMed] [Google Scholar]
  13. Frick A. Proximal tubular reabsorption of inorganic phosphate during saline infusion in the rat. Am J Physiol. 1972 Nov;223(5):1034–1040. doi: 10.1152/ajplegacy.1972.223.5.1034. [DOI] [PubMed] [Google Scholar]
  14. Frick A. Reabsorption of inorganic phosphate in the rat kidney. I. Saturation of transport mechanism. II. Suppression of fractional phosphate reabsorption due to expansion of extracellular fluid volume. Pflugers Arch. 1968;304(4):351–364. doi: 10.1007/BF00587710. [DOI] [PubMed] [Google Scholar]
  15. Fulop M., Brazeau P. The phosphaturic effect of sodium bicarbonate and acetazolamide in dogs. J Clin Invest. 1968 May;47(5):983–991. doi: 10.1172/JCI105813. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Hellman D. E., Au W. Y., Bartter F. C. Evidence for a direct effect of parathyroid hormone on urinary acidification. Am J Physiol. 1965 Sep;209(3):643–650. doi: 10.1152/ajplegacy.1965.209.3.643. [DOI] [PubMed] [Google Scholar]
  17. Kokko J. P. Proximal tubule potential difference. Dependence on glucose on glucose, HCO 3 , and amino acids. J Clin Invest. 1973 Jun;52(6):1362–1367. doi: 10.1172/JCI107308. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Kuntziger H., Amiel C., Gaudebout C. Phosphate handling by the rat nephron during saline diuresis. Kidney Int. 1972 Dec;2(6):318–323. doi: 10.1038/ki.1972.115. [DOI] [PubMed] [Google Scholar]
  19. LOTSPEICH W. D., MALVIN R. L. Relation between tubular transport of inorganic phosphate and bicarbonate in the dog. Am J Physiol. 1956 Sep;187(1):51–56. doi: 10.1152/ajplegacy.1956.187.1.51. [DOI] [PubMed] [Google Scholar]
  20. MOSTELLAR M. E., TUTTLE E. P., Jr EFFECTS OF ALKALOSIS ON PLASMA CONCENTRATION AND URINARY EXCRETION OF INORGANIC PHOSPHATE IN MAN. J Clin Invest. 1964 Jan;43:138–149. doi: 10.1172/JCI104888. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Maesaka J. K., Levitt M. F., Abramson R. G. Effect of saline infusion on phosphate transport in intact and thyroparathyroidectomized rats. Am J Physiol. 1973 Dec;225(6):1421–1429. doi: 10.1152/ajplegacy.1973.225.6.1421. [DOI] [PubMed] [Google Scholar]
  22. Malnic G., Vieira F. L. The antimony microelectrode in kidney micropuncture. Yale J Biol Med. 1972 Jun-Aug;45(3-4):356–367. [PMC free article] [PubMed] [Google Scholar]
  23. Murayama Y., Morel F., Le Grimellec C. Phosphate, calcium and magnesium transfers in proximal tubules and loops of Henle, as measured by single nephron microperfusion experiments in the rat. Pflugers Arch. 1972;333(1):1–16. doi: 10.1007/BF00586037. [DOI] [PubMed] [Google Scholar]
  24. NORDIN B. E. The effect of intravenous parathyroid extract on urinary pH, bicarbonate and electrolyte excretion. Clin Sci. 1960 May;19:311–319. [PubMed] [Google Scholar]
  25. Puschett J. B., Goldberg M. The relationship between the renal handling of phosphate and bicarbonate in man. J Lab Clin Med. 1969 Jun;73(6):956–969. [PubMed] [Google Scholar]
  26. Rodriguez H. J., Walls J., Yates J., Klahr S. Effects of acetazolamide on the urinary excretion of cyclic AMP and on the activity of renal adenyl cyclase. J Clin Invest. 1974 Jan;53(1):122–130. doi: 10.1172/JCI107529. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. STRICKLER J. C., THOMPSON D. D., KLOSE R. M., GIEBISCH G. MICROPUNCTURE STUDY OF INORGANIC PHOSPHATE EXCRETION IN THE RAT. J Clin Invest. 1964 Aug;43:1596–1607. doi: 10.1172/JCI105035. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Staum B. B., Hamburger R. J., Goldberg M. Tracer microinjection study of renal tubular phosphate reabsorption in the rat. J Clin Invest. 1972 Sep;51(9):2271–2276. doi: 10.1172/JCI107036. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Vieira F. L., Malnic G. Hydrogen ion secretion by rat renal cortical tubules as studied by an antimony microelectrode. Am J Physiol. 1968 Apr;214(4):710–718. doi: 10.1152/ajplegacy.1968.214.4.710. [DOI] [PubMed] [Google Scholar]
  30. WINDHAGER E. E., GIEBISCH G. Micropuncture study of renal tubular transfer of sodium chloride in the rat. Am J Physiol. 1961 Mar;200:581–590. doi: 10.1152/ajplegacy.1961.200.3.581. [DOI] [PubMed] [Google Scholar]
  31. Wen S. F. Micropuncture studies of phosphate transport in the proximal tubule of the dog. The relationship to sodium reabsorption. J Clin Invest. 1974 Jan;53(1):143–153. doi: 10.1172/JCI107532. [DOI] [PMC free article] [PubMed] [Google Scholar]
  32. Yarger W. E., Aynedjian H. S., Bank N. A micropuncture study of postobstructive diuresis in the rat. J Clin Invest. 1972 Mar;51(3):625–637. doi: 10.1172/JCI106852. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Journal of Clinical Investigation are provided here courtesy of American Society for Clinical Investigation

RESOURCES