Advertisement

Pflügers Archiv

, Volume 365, Issue 1, pp 29–36 | Cite as

Effects of Na and K ions on the active Na transport in guinea-pig auricles

  • Helfried Günther Glitsch
  • Hermann Pusch
  • Klaus Venetz
Article

Summary

  1. 1.

    The effect of Na and K ions on active Na transport was studied in guinea-pig auricles by means of flame photometry.

     
  2. 2.

    The Na influx into preparations rewarmed in Tyrode's solution after cooling was estimated to be about 1.05 mmole/l fibre water·min ((l.f.w.·min) or c. 8 pmole/cm2·s. Intracellular Na ions enhanced the active Na efflux over a wide range of concentrations. A decrease in the extracellular Na concentration ([Na] o ) had no major effect on the active Na efflux.

     
  3. 3.

    Extracellular K ions initiated an active Na efflux from rewarmed auricles with an elevated [Na] i over a narrow range of K concentrations ([K] o ).

     
  4. 4.

    Assuming Michaelis-Menten kinetics the maximal active Na efflux activated by internal Na ions was calculated to be about 4 mmole/l.f.w.·min (30 pmole/cm2·s). Half maximal Na efflux occurred at about 22 mmole/l.f.w. [Na] i . The maximal K-activated active Na efflux was deduced to be about 3.7 mmole/l.f.w.·min (28 pmole/cm2·s) and was half maximal at a [K] o of about 0.2 mM.

     
  5. 5.

    It is tentatively concluded that the maximal active Na efflux from guinea-pig atria is 3–4 times larger than the physiological flux. Under normal conditions active Na efflux in heart is mainly regulated by variations of [Na] i .

     

Key words

Cardiac muscle Active Na transport Na and K ions 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Baker, P. F., Connelly, C. M.: Some properties of the external activation site of the Na pump in crab nerve. J. Physiol. (Lond.)185, 270–297 (1966)Google Scholar
  2. Bonting, S. L.: Sodium-potassium activated adenosinetriphosphatase and cation transport. In: Membranes and ion transport, Vol. 1, (E. E. Bittar, ed.), pp. 257–363. London-New York-Sydney-Toronto: John Wiley & Sons Ltd. 1970Google Scholar
  3. Bosteels, S., Carmeliet, E.: Estimation of intracellular Na concentration and transmembrane Na flux in cardiac Purkyně fibres. Pflügers Arch.336, 35–47 (1972a)Google Scholar
  4. Bosteels, S., Carmeliet, E.: The components of the sodium efflux in cardiac Purkyně fibres. Pflügers Arch.336, 48–59 (1972b)Google Scholar
  5. Bosteels, S., Vleugels, A., Carmeliet, E.: Choline permeability in cardiac muscle cells of the cat. J. gen. Physiol.55, 602–619 (1970)Google Scholar
  6. Erdmann, E., Bolte, H.-D., Lüderitz, B.: The (Na++K+)-ATPase activity of guinea pig heart muscle in potassium deficiency. Arch. Biochem. Biophys.145, 121–125 (1971)Google Scholar
  7. Garrahan, P. J., Glynn, I. M.: The sensitivity of the sodium pump to external sodium. J. Physiol. (Lond.)192, 175–188 (1967)Google Scholar
  8. Glitsch, H. G.: Über das Membranpotential des Meerschweinchenvorhofes nach Hypothermie. Pflügers Arch.307, 29–46 (1969)Google Scholar
  9. Glitsch, H. G.: Activation of the electrogenic sodium pump in guinea-pig auricles by internal sodium ions. J. Physiol. (Lond.)220, 565–582 (1972)Google Scholar
  10. Glitsch, H. G.: Active Na efflux from guinea-pig atria with various intracellular Na concentrations. Pflügers Arch.355 Suppl., R 11 (1975)Google Scholar
  11. Glitsch, H. G., Pusch, H., Venetz, K.: Effect of extracellular Na and K on the active Na efflux from Na loaded cardiac cells. Pflügers Arch.359, R 22 (1975)Google Scholar
  12. Glynn, I. M.: Membrane adenosine triphosphatase and cation transport. Brit. med. Bull.24, 165–169 (1968)Google Scholar
  13. Haas, H. G., Glitsch, H. G., Trautwein, W.: Natrium-Fluxe am Vorhof des Froschherzens. Pflügers Arch.277, 36–47 (1963)Google Scholar
  14. Haas, H. G., Glitsch, H. G., Kern, R.: Zum Problem der gegenseitigen Beeinflussung der Ionenfluxe am Myokard. Pflügers Arch.281, 282–299 (1964)Google Scholar
  15. Haas, H. G., Hantsch, F., Otter, H. P., Siegel, G.: Untersuchungen zum Problem des aktiven K- und Na-Transports am Myokard. Pflügers Arch.294, 144–168 (1967)Google Scholar
  16. Hiraoka, M., Hecht, H. H.: Recovery from hypothermia in cardiac Purkinje fibers: Considerations for an electrogenic mechanism. Pflügers Arch.339, 25–36 (1973)Google Scholar
  17. Johnson, J. A.: Sodium exchange in the frog heart ventricle. Amer. J. Physiol.191, 487–492 (1957)Google Scholar
  18. Noma, A., Irisawa, H.: Contribution of an electrogenic sodium pump to the membrane potential in rabbit sinoatrial node cells. Pflügers Arch.358, 289–301 (1975)Google Scholar
  19. Page, E., Storm, S. R.: Cat heart muscle in Vitro. VIII. Active transport of sodium in papillary muscles. J. gen. Physiol.48, 957–972 (1965)Google Scholar
  20. Page, E., Goerke, R. J., Storm, S. R.: Cat heart muscle in Vitro. IV. Inhibition of transport in quiescent muscles. J. gen. Physiol.47, 531–543 (1964)Google Scholar
  21. Portius, H. J., Repke, K. R. H.: Eigenschaften und Funktion des Na++K+-aktivierten, Mg2+-abhängigen Adenosintriphosphat Phosphohydrolase-Systems des Herzmuskels. Acta biol. med. german.19, 907–938 (1967)Google Scholar
  22. Sjodin, R. A.: The kinetics of sodium extrusion in striated muscle as functions of the external sodium and potassium ion concentrations. J. gen. Physiol.57, 164–187 (1971)Google Scholar
  23. Winegrad, S., Shanes, A. M.: Calcium flux and contractility in guinea pig atria. J. gen. Physiol.45, 371–394 (1962)Google Scholar

Copyright information

© Springer-Verlag 1976

Authors and Affiliations

  • Helfried Günther Glitsch
    • 1
  • Hermann Pusch
    • 1
  • Klaus Venetz
    • 1
  1. 1.Lehrstuhl für Zellphysiologie and SFB 114 BionachRuhr-Universität BochumBochum-QuerenburgGermany

Personalised recommendations