Fluoride renal clearance: a pH dependent event

Gary M. Whitford, D. H. Pashley, G. I. Stringer

Research output: Contribution to journalArticle

94 Citations (Scopus)

Abstract

The renal clearance of fluoride (Cf) was studied in pentobarbital anesthetized rats. Urine flow rate and chloride clearance, previously thought to be the main determinants of Cf, were readily dissociated from Cf. Neither the clearance of sodium nor the excretion of potassium correlated consistently with Cf. In experiments designed to manipulate urinary pH, viz., the administration of NaHCO3 or NH4Cl, acetazolamide, and mannitol, Cf correlated closely with urinary pH. At a urinary pH of 5.0-5.6, Cf/GFR averaged less than 5% while at a urinary pH of approximately 7.6, mean Cf/GFR exceeded 65%. The data suggest that 35-45% of the filtered fluoride is reabsorbed in the proximal tubule, regardless of the final urinary pH, while in acidosis the majority of fluoride reabsorption occurs in the distal nephron. The results suggest that the tubular reabsorption of fluoride is inversely related to tubular pH. Fluoride reabsorption seems to occur by nonionic diffusion, apparently as hydrogen fluoride. Depending on local pH gradients, it may occur along the entire nephron.

Original languageEnglish (US)
Pages (from-to)527-532
Number of pages6
JournalAmerican Journal of Physiology
Volume230
Issue number2
StatePublished - Dec 1 1976

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Fluorides
Kidney
Nephrons
Hydrofluoric Acid
Acetazolamide
Proton-Motive Force
Mannitol
Pentobarbital
Acidosis
Chlorides
Potassium
Sodium
Urine

ASJC Scopus subject areas

  • Medicine(all)

Cite this

Whitford, G. M., Pashley, D. H., & Stringer, G. I. (1976). Fluoride renal clearance: a pH dependent event. American Journal of Physiology, 230(2), 527-532.

Fluoride renal clearance : a pH dependent event. / Whitford, Gary M.; Pashley, D. H.; Stringer, G. I.

In: American Journal of Physiology, Vol. 230, No. 2, 01.12.1976, p. 527-532.

Research output: Contribution to journalArticle

Whitford, GM, Pashley, DH & Stringer, GI 1976, 'Fluoride renal clearance: a pH dependent event', American Journal of Physiology, vol. 230, no. 2, pp. 527-532.
Whitford, Gary M. ; Pashley, D. H. ; Stringer, G. I. / Fluoride renal clearance : a pH dependent event. In: American Journal of Physiology. 1976 ; Vol. 230, No. 2. pp. 527-532.
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