Modeling the effects of a variable gap junction resistance in a pair of cardiac cells

In cardiac tissue, the propagation of an action potential is conditioned by the degree of intercellular coupling. The electrical conductance is known to vary with the frequency of action potential generation, as well as with the intracellular calcium concentration. The present paper describes a calcium dependent model for the gap junction resistance, and examines the entrainment of a pair of cells with external pacing applied to one of them. At low frequency, both cells were well coupled and behaved as a single unit. At high frequency, the degree of coupling decreased, giving rise to complex dynamic patterns