Cardiac Action Potentials, Ion Channels, and Gap Junctions

  • Jacques M. T. de Bakker
  • Harold V. M. van Rijen


Interplay between various ion channels in the membrane of cardiomyocytes is responsible for depolarization and repolarization of the heart cells, whereas cell-to-cell coupling, mediated by gap junction proteins, is involved in propagation of the action potential through the heart. In this chapter, the different phases of the action potential of heart cells are discussed and the role and characteristics of the most important ion channels that are active during these phases are conferred. Differences in the expression of the various ion and gap junction channels under normal conditions are described. Also discussed are changes in ion and gap junction channel expression and distribution that occur in cardiac disease. Finally, the role of ligand-gated and stretch-activated ion channels is addressed briefly.


Sodium Channel Action Potential Duration Sodium Current Plateau Phase Arrhythmogenic Right Ventricular Cardiomyopathy 
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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Jacques M. T. de Bakker
    • 1
  • Harold V. M. van Rijen
  1. 1.Department of Experimental CardiologyAcademic Medical CenterAmsterdamThe Netherlands

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