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. 1971 Aug 1;58(2):131–144. doi: 10.1085/jgp.58.2.131

Effect of Changes in Transepithelial Transport on the Uptake of Sodium across the Outer Surface of the Frog Skin

Thomas U L Biber 1
PMCID: PMC2226015  PMID: 5559619

Abstract

The unidirectional sodium, uptake at the outer surface of the frog skin was measured by the method described by Biber and Curran (8). With bathing solutions containing 6 mM NaCl there is a good correlation between sodium uptake and short-circuit current (SCC) measured simultaneously except that the average uptake is about 40% higher than the average SCC. The discrepancy between uptake and SCC increases approximately in proportion to an increase in sodium concentration of the bathing solutions. Amiloride inhibits the unidirectional sodium uptake by 21 and 69% at a sodium concentration of 115 and 6 mM, respectively. This indicates that amiloride acts on the entry step of sodium but additional effects cannot be excluded. The sodium, uptake is not affected by 10-4 M ouabain at a sodium concentration of 115 mM but is inhibited by 40% at a sodium concentration of 6 mM. Replacement of air by nitrogen leads to a 40% decrease of sodium uptake at a sodium concentration of 6 mM. The results support the view proposed previously (8) that the sodium uptake is made up of two components, a linear component which is, essentially, not involved in transepithelial movement of sodium and a saturating component which reflects changes in transepithelial transport. Amiloride, seems largely to affect the saturating component.

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Selected References

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

  1. ANDERSEN B., ZERAHN K. METHOD FOR NON-DESTRUCTIVE DETERMINATION OF THE SODIUM TRANSPORT POOL IN FROG SKIN WITH RADIOSODIUM. Acta Physiol Scand. 1963 Dec;59:319–329. doi: 10.1111/j.1748-1716.1963.tb02747.x. [DOI] [PubMed] [Google Scholar]
  2. Bentley P. J. Amiloride: a potent inhibitor of sodium transport across the toad bladder. J Physiol. 1968 Mar;195(2):317–330. doi: 10.1113/jphysiol.1968.sp008460. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Biber T. U., Chez R. A., Curran P. F. Na transport across frog skin at low external Na concentrations. J Gen Physiol. 1966 Jul;49(6):1161–1176. doi: 10.1085/jgp.0491161. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Biber T. U., Curran P. F. Direct measurement of uptake of sodium at the outer surface of the frog skin. J Gen Physiol. 1970 Jul;56(1):83–99. doi: 10.1085/jgp.56.1.83. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. CEREIJIDO M., CURRAN P. F. INTRACELLULAR ELECTRICAL POTENTIALS IN FROG SKIN. J Gen Physiol. 1965 Mar;48:543–557. doi: 10.1085/jgp.48.4.543. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. CEREIJIDO M., HERRERA F. C., FLANIGAN W. J., CURRAN P. F. THE INFLUENCE OF NA CONCENTRATION ON NA TRANSPORT ACROSS FROG SKIN. J Gen Physiol. 1964 May;47:879–893. doi: 10.1085/jgp.47.5.879. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Crabbé J., Ehrlich E. N. Amiloride and the mode of action of aldosterone on sodium transport across toad bladder and skin. Pflugers Arch. 1968;304(3):284–296. doi: 10.1007/BF00592131. [DOI] [PubMed] [Google Scholar]
  8. Dörge A., Nagel W. Effect of amiloride on sodium transport in frog skin. II. Sodium transport pool and unidirectional fluxes. Pflugers Arch. 1970;321(2):91–101. doi: 10.1007/BF00586365. [DOI] [PubMed] [Google Scholar]
  9. Ehrlich E. N., Crabbé J. The mechanism of action of amipramizide. Pflugers Arch. 1968;302(1):79–96. doi: 10.1007/BF00586783. [DOI] [PubMed] [Google Scholar]
  10. Eigler J., Kelter J., Renner E. Wirkungscharakteristika eines neuen Acylguanidins--Amiloride-HCL (MK 870)--an der isolierten Haut von Amphibien. Klin Wochenschr. 1967 Jul 15;45(14):737–738. doi: 10.1007/BF01746103. [DOI] [PubMed] [Google Scholar]
  11. KIDDER G. W., 3rd, CEREIJIDO M., CURRAN P. F. TRANSIENT CHANGES IN ELECTRICAL POTENTIAL DIFFERENCES ACROSS FROG SKIN. Am J Physiol. 1964 Oct;207:935–940. doi: 10.1152/ajplegacy.1964.207.4.935. [DOI] [PubMed] [Google Scholar]
  12. KOEFOED-JOHNSEN V., USSING H. H. The nature of the frog skin potential. Acta Physiol Scand. 1958 Jun 2;42(3-4):298–308. doi: 10.1111/j.1748-1716.1958.tb01563.x. [DOI] [PubMed] [Google Scholar]
  13. Rotunno C. A., Vilallonga F. A., Fernández M., Cereijido M. The penetration of sodium into the epithelium of the frog skin. J Gen Physiol. 1970 Jun;55(6):716–735. doi: 10.1085/jgp.55.6.716. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Salako L. A., Smith A. J. Effects of amiloride on active sodium transport by the isolated frog skin: evidence concerning site of action. Br J Pharmacol. 1970 Apr;38(4):702–718. doi: 10.1111/j.1476-5381.1970.tb09878.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Zerahn K. Nature and localization of the sodium pool during active transport in the isolated frog skin. Acta Physiol Scand. 1969 Nov;77(3):272–281. doi: 10.1111/j.1748-1716.1969.tb04572.x. [DOI] [PubMed] [Google Scholar]

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