Electrical interactions among real cardiac cells and cell models in a linear strand

• Published in: American journal of physiology. Heart and circulatory physiology 1999-02, Vol.276 (2), p.H391-H400
• Main Authors: Wagner, Mary B, Namiki, Takao, Wilders, Ronald, Joyner, Ronald W, Jongsma, Habo J, Verheijck, E. Etienne, Kumar, Rajiv, Golod, David A, Goolsby, William N, van Ginneken, Antoni C. G
• Format: Article
• Language: English
• ISSN: 0363-6135; 1522-1539
• DOI: 10.1152/ajpheart.1999.276.2.h391

1  Todd Franklin Cardiac Research Laboratory, The Children's Heart Center, Department of Pediatrics, Emory University, Atlanta, Georgia 30322; 2  Department of Medical Physiology and Sports Medicine, Utrecht University, 3584 CG Utrecht; and 3  Department of Physiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands Previous work with model systems for action potential conduction have been restricted to conduction between two real cells or conduction between a model cell and a real cell. The inclusion of additional elements to make a linear strand has allowed us to investigate the interactions between cells at a higher level of complexity. When, in the simplest case of a linear strand of three elements, the conductance between elements 2  and 3  ( G C2 ) is varied, this affects the success or failure of propagation between elements 1  and 2  (coupled by G C1 ) as well as the success or failure of propagation between elements 2  and 3 . Several major features were illustrated. 1 ) When G C1 was only slightly greater than the coupling conductance required for successful propagation between a model cell and a real cell, addition of a third element of the strand either prevented conduction from element 1  to element 2  (when G C2 was high) or allowed conduction from element 1  to element 2  but not conduction from element 2  to element 3  (when G C2 was low). 2 ) For higher levels of G C1 , there was an allowable "window" of values of G C2 for successful conduction from element 1  through to element 3 . The size of this allowable window of G C2 values increased with increasing values of G C1 , and this increase was produced by increases in the upper bound of G C2 values. 3 ) When the size of the central element of the strand was reduced, this facilitated conduction through the strand, increasing the range of the allowable window of G C2 values. The overall success or failure of conduction through a structure of cells that has a spatially inhomogeneous distribution of coupling conductances cannot be predicted simply by the average or the minimum value of coupling conductance but may depend on the actual spatial distribution of these conductances. coupling conductance; cardiac action potential conduction