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. 1973 Jul 1;62(1):1–24. doi: 10.1085/jgp.62.1.1

Response of the Frog Skin to Steady-State Voltage Clamping

II. The active pathway

Lazaro J Mandel 1, Peter F Curran 1
PMCID: PMC2226107  PMID: 4543671

Abstract

Active Na transport across frog skin was separated from passive Na movement utilizing urea influx as a measure of passive (shunt) permeability. In this manner, the response of the overall active Na transport system to an applied potential was determined over a range from +200 mV to -100 mV. Active Na transport displays saturation as a function of applied potential, and both the level of saturation and the potential at which it is achieved are functions of the Na concentration in the external solution. The saturation with potential appears to involve a different step in the transport process than the saturation of Na flux as a function of external Na concentration. The observations can be qualitatively described by either a one-barrier or two-barrier model of the Na transport system.

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Selected References

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

  1. Aceves J., Erlij D. Sodium transport across the isolated epithelium of the frog skin. J Physiol. 1971 Jan;212(1):195–210. doi: 10.1113/jphysiol.1971.sp009317. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. 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]
  3. 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]
  4. Biber T. U. Effect of changes in transepithelial transport on the uptake of sodium across the outer surface of the frog skin. J Gen Physiol. 1971 Aug;58(2):131–144. doi: 10.1085/jgp.58.2.131. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Biber T. U., Sanders M. L. Influence of transepithelial potential difference on the sodium uptake at the outer surface of the isolated frog skin. J Gen Physiol. 1973 May;61(5):529–551. doi: 10.1085/jgp.61.5.529. [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. Candia O. A. The hyperpolarizing region of the current-voltage curve in frog skin. Biophys J. 1970 Apr;10(4):323–344. doi: 10.1016/S0006-3495(70)86305-6. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Cereijido M., Rotunno C. A. Fluxes and distribution of sodium in frog skin. A new model. J Gen Physiol. 1968 May;51(5 Suppl):280S+–280S+. [PubMed] [Google Scholar]
  9. Civan M. M. Effects of active sodium transport on current-voltage relationship of toad bladder. Am J Physiol. 1970 Jul;219(1):234–245. doi: 10.1152/ajplegacy.1970.219.1.234. [DOI] [PubMed] [Google Scholar]
  10. Conti F., Eisenman G. The steady-state properties of an ion exchange membrane with mobile sites. Biophys J. 1966 May;6(3):227–246. doi: 10.1016/S0006-3495(66)86653-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Erlij D. Salt transport across isolated frog skin. Philos Trans R Soc Lond B Biol Sci. 1971 Aug 20;262(842):153–161. doi: 10.1098/rstb.1971.0086. [DOI] [PubMed] [Google Scholar]
  12. FINKELSTEIN A. ELECTRICAL EXCITABILITY OF ISOLATED FROG SKIN AND TOAD BLADDER. J Gen Physiol. 1964 Jan;47:545–565. doi: 10.1085/jgp.47.3.545. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Fishman H. M., Macey R. I. The N-shaped current-potential characteristic in frog skin. I. Time development during step voltage clamp. Biophys J. 1969 Feb;9(2):127–139. doi: 10.1016/S0006-3495(69)86374-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Frizzell R. A., Schultz S. G. Ionic conductances of extracellular shunt pathway in rabbit ileum. Influence of shunt on transmural sodium transport and electrical potential differences. J Gen Physiol. 1972 Mar;59(3):318–346. doi: 10.1085/jgp.59.3.318. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. García Romeu F., Salibián A., Pezzani-Hernádez S. The nature of the in vivo sodium and chloride uptake mechanisms through the epithelium against sodium and of bicarbonate against chloride. J Gen Physiol. 1969 Jun;53(6):816–835. doi: 10.1085/jgp.53.6.816. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. 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]
  17. MACROBBIE E. A., USSING H. H. Osmotic behaviour of the epithelial cells of frog skin. Acta Physiol Scand. 1961 Nov-Dec;53:348–365. doi: 10.1111/j.1748-1716.1961.tb02293.x. [DOI] [PubMed] [Google Scholar]
  18. Mandel L. J., Curran P. F. Response of the frog skin to steady-state voltage clamping. I. The shunt pathway. J Gen Physiol. 1972 May;59(5):503–518. doi: 10.1085/jgp.59.5.503. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. 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]
  20. USSING H. H., ZERAHN K. Active transport of sodium as the source of electric current in the short-circuited isolated frog skin. Acta Physiol Scand. 1951 Aug 25;23(2-3):110–127. doi: 10.1111/j.1748-1716.1951.tb00800.x. [DOI] [PubMed] [Google Scholar]
  21. Walker J. L., Jr, Eisenman G. A test of the theory of the steady-state properties of an ion exchange membrane with mobile sites and dissociated counterions. Biophys J. 2008 Dec 31;6(4):513–533. doi: 10.1016/S0006-3495(66)86673-0. [DOI] [PMC free article] [PubMed] [Google Scholar]

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