Display options
Share it on

Naunyn Schmiedebergs Arch Pharmacol. 1987 Mar;335(3):321-5. doi: 10.1007/BF00172804.

Blockage of the fast sodium current by dimethindene in frog auricular fibres.

Naunyn-Schmiedeberg's archives of pharmacology

J Mészáros, R Markó, K Kelemen, V Kecskeméti

PMID: 2438562 DOI: 10.1007/BF00172804

Abstract

The effect of dimethindene (DMI) on action potential and fast inward Na current (INa) of frog atrial fibres was studied using double sucrose gap voltage-clamp technique. DMI reduced the amplitude and maximum rate of rise of the action potentials without altering the resting membrane potential. The drug inhibited the fast Na conductance in a concentration-dependent manner, without changing the reversal potential. The shape of the current-voltage curve along the voltage axis remained unchanged in the presence of DMI. The time to peak of the INa was not significantly altered by the drug whereas the rate of the INa inactivation (tau h) was slowed. DMI shifted the steady-state inactivation curve of INa (h infinity) to more negative potentials, and increased the reactivation time constant of the sodium system (tau r). The inhibition of INa was use-dependent. The results suggest that DMI interacts with the inactivation mechanism of the sodium channel of the frog myocardium, and explain its favourable antiarrhythmic activity.

References

  1. J Physiol. 1955 Sep 28;129(3):568-82 - PubMed
  2. Biophys J. 1984 Jul;46(1):15-27 - PubMed
  3. J Physiol. 1976 Jul;258(3):615-29 - PubMed
  4. Circ Res. 1975 Jul;37(1):20-9 - PubMed
  5. Toxicol Appl Pharmacol. 1961 Sep;3:534-44 - PubMed
  6. Pflugers Arch. 1983 Dec;399(4):321-35 - PubMed
  7. Agents Actions. 1977 Mar;7(1):97-101 - PubMed
  8. Biophys J. 1977 Mar;17(3):275-9 - PubMed
  9. Circ Res. 1984 Jun;54(6):636-51 - PubMed
  10. Biophys J. 1974 Sep;14(9):627-43 - PubMed
  11. Pharmacol Rev. 1978 Mar;30(1):5-63 - PubMed
  12. Pflugers Arch. 1971;323(2):141-57 - PubMed
  13. Biophys J. 1980 May;30(2):327-49 - PubMed
  14. Naunyn Schmiedebergs Arch Pharmakol. 1971;269(2):199-212 - PubMed
  15. J Gen Physiol. 1983 May;81(5):613-42 - PubMed
  16. Orv Hetil. 1982 Sep 26;123(39):2405-7 - PubMed
  17. J Physiol. 1952 Aug;117(4):500-44 - PubMed
  18. Experientia. 1983 Apr 15;39(4):400-2 - PubMed
  19. Biochim Biophys Acta. 1977 Nov 14;472(3-4):373-98 - PubMed
  20. J Physiol. 1970 Mar;207(1):165-90 - PubMed
  21. J Gen Physiol. 1977 Apr;69(4):497-515 - PubMed
  22. J Physiol. 1974 Aug;240(3):775-806 - PubMed
  23. J Pharmacol Exp Ther. 1975 Nov;195(2):225-36 - PubMed
  24. Eur J Pharmacol. 1979 May 1;55(3):225-32 - PubMed
  25. Biophys J. 1975 Oct;15(10):1069-85 - PubMed
  26. Eur J Pharmacol. 1983 Dec 9;96(1-2):45-52 - PubMed
  27. Pflugers Arch Gesamte Physiol Menschen Tiere. 1968;301(2):91-108 - PubMed
  28. Annu Rev Pharmacol Toxicol. 1984;24:387-423 - PubMed
  29. Pflugers Arch. 1972;335(4):309-22 - PubMed
  30. Pharmacol Ther B. 1975;1(1):115-38 - PubMed

Substances

MeSH terms

Publication Types

LinkOut - more resources