Skip to main content
The Journal of General Physiology logoLink to The Journal of General Physiology
. 1986 Mar 1;87(3):425–442. doi: 10.1085/jgp.87.3.425

Effect of sodium on amiloride- and triamterene-induced current fluctuations in isolated frog skin

PMCID: PMC2217608  PMID: 2420917

Abstract

The apparent association constants of two agents, amiloride and triamterene, that block the Na-selective channel of apical membrane of frog skin are shown to decrease as the Na concentration is increased in the apical bathing solution in isolated skin of the frog, Rana temporaria, Rana esculenta, and Rana pipiens. These results were obtained in "normally polarized" skins. These effects were independent of the anion used (chloride or methylsulfate) or the cation used as the Na substitute (Tris, DDA, or K ion). When NaCl was replaced with mannitol, the Na effect on the amiloride association rate constant persisted, which shows that ionic strength was not critically involved. The amiloride corner frequency was unaffected when the clamp potential was altered from +100 to -60 mV. The Na dependence was greatly attenuated or absent when the serosal surface was bathed in 120 mM K Ringer's, an effect that appears to be attributable to some pharmacological effect of high serosal K. A previously described three- state model is used to analyze the inhibitory effect of Na on the blocker association rate constant.

Full Text

The Full Text of this article is available as a PDF (1.0 MB).

Selected References

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

  1. Benos D. J., Mandel L. J., Balaban R. S. On the mechanism of the amiloride-sodium entry site interaction in anuran skin epithelia. J Gen Physiol. 1979 Mar;73(3):307–326. doi: 10.1085/jgp.73.3.307. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Benos D. J., Reyes J., Shoemaker D. G. Amiloride fluxes across erythrocyte membranes. Biochim Biophys Acta. 1983 Sep 21;734(1):99–104. doi: 10.1016/0005-2736(83)90080-9. [DOI] [PubMed] [Google Scholar]
  3. Cuthbert A. W. Importance of guanidinium groups of blocking sodium channels in epithelia. Mol Pharmacol. 1976 Nov;12(6):945–957. [PubMed] [Google Scholar]
  4. Cuthbert A. W., Wilson S. A. Mechanisms for the effects of acetylcholine on sodium transport in frog skin. J Membr Biol. 1981 Mar 15;59(1):65–75. doi: 10.1007/BF01870822. [DOI] [PubMed] [Google Scholar]
  5. Frehland E., Hoshiko T., Machlup S. Competitive blocking of apical sodium channels in epithelia. Biochim Biophys Acta. 1983 Aug 10;732(3):636–646. doi: 10.1016/0005-2736(83)90241-9. [DOI] [PubMed] [Google Scholar]
  6. Fuchs W., Larsen E. H., Lindemann B. Current-voltage curve of sodium channels and concentration dependence of sodium permeability in frog skin. J Physiol. 1977 May;267(1):137–166. doi: 10.1113/jphysiol.1977.sp011805. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Grosso A., Brown D., de Sousa R. C. Cellular and membrane events involved in the K-induced increase in water permeability of toad skin. Pflugers Arch. 1982 Nov 1;395(2):145–151. doi: 10.1007/BF00584728. [DOI] [PubMed] [Google Scholar]
  8. Hall W. J., O'Regan M. G., Quigley C. A role for endogneous prostaglandins in the short-circuit current responses to osmolal changes in isolated frog skin. J Physiol. 1977 Aug;270(1):223–238. doi: 10.1113/jphysiol.1977.sp011948. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Helman S. I., Cox T. C., Van Driessche W. Hormonal control of apical membrane Na transport in epithelia. Studies with fluctuation analysis. J Gen Physiol. 1983 Aug;82(2):201–220. doi: 10.1085/jgp.82.2.201. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Helman S. I., Miller D. A. In vitro techniques for avoiding edge damage in studies of frog skin. Science. 1971 Jul 9;173(3992):146–148. doi: 10.1126/science.173.3992.146. [DOI] [PubMed] [Google Scholar]
  11. Lindemann B. Fluctuation analysis of sodium channels in epithelia. Annu Rev Physiol. 1984;46:497–515. doi: 10.1146/annurev.ph.46.030184.002433. [DOI] [PubMed] [Google Scholar]
  12. Lindemann B., Van Driessche W. Sodium-specific membrane channels of frog skin are pores: current fluctuations reveal high turnover. Science. 1977 Jan 21;195(4275):292–294. doi: 10.1126/science.299785. [DOI] [PubMed] [Google Scholar]
  13. Rick R., Dörge A., von Arnim E., Thurau K. Electron microprobe analysis of frog skin epithelium: evidence for a syncytial sodium transport compartment. J Membr Biol. 1978 Mar 20;39(4):313–331. doi: 10.1007/BF01869897. [DOI] [PubMed] [Google Scholar]
  14. SHARE L., USSING H. H. EFFECT OF POTASSIUM ON THE MOVEMENT OF WATER ACROSS THE ISOLATED AMPHIBIAN SKIN. Acta Physiol Scand. 1965 May-Jun;64:109–118. doi: 10.1111/j.1748-1716.1965.tb04159.x. [DOI] [PubMed] [Google Scholar]
  15. Van Driessche W., Erlij D. Noise analysis of inward and outward Na+ currents across the apical border of ouabain-treated frog skin. Pflugers Arch. 1983 Aug;398(3):179–188. doi: 10.1007/BF00657149. [DOI] [PubMed] [Google Scholar]
  16. Van Driessche W., Lindemann B. Concentration dependence of currents through single sodium-selective pores in frog skin. Nature. 1979 Nov 29;282(5738):519–520. doi: 10.1038/282519a0. [DOI] [PubMed] [Google Scholar]
  17. Van Driessche W., Zeiske W. Spontaneous fluctuations of potassium channels in the apical membrane of frog skin. J Physiol. 1980 Feb;299:101–116. doi: 10.1113/jphysiol.1980.sp013113. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Zeiske W., Wills N. K., Van Driessche W. Na+ channels and amiloride-induced noise in the mammalian colon epithelium. Biochim Biophys Acta. 1982 May 21;688(1):201–210. doi: 10.1016/0005-2736(82)90595-8. [DOI] [PubMed] [Google Scholar]

Articles from The Journal of General Physiology are provided here courtesy of The Rockefeller University Press

RESOURCES