Pflügers Archiv

, Volume 390, Issue 1, pp 102–106 | Cite as

Inhibition of transient outward current by intracellular ion substitution unmasks slow inward calcium current in cardiac Purkinje fibers

  • Eduardo Marban
Excitable Tissues and Central Nervous Physiology Letters and Notes


The ionophore nystatin was used to replace intracellular K+ with Cs+ in calf Purkinje fibers. Such replacement inhibited the transient outward current, and unmasked a large slow inward current (Isi). These results support the involvement of K+ as a charge carrier of the transient outward current, and suggest a method for better analysis of Isi.

Key words

calcium current Purkinje fiber voltage clamp nystatin cesium 


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Copyright information

© Springer-Verlag 1981

Authors and Affiliations

  • Eduardo Marban
    • 1
  1. 1.Department of PhysiologyYale UniversityNew HavenUSA

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