The Effect of Gap Junction Conductance onSynchronisation of Sinoatrial Node Central Cells

摘要

The orderly propagation of electrical excitation through the sinoatrial node (SAN) in the heartis fundamental to its pacemaking properties. This is achieved via the synchronization of the electricalcell cycle of the nearest neighbour cells within the node. This is mediated via gap junction proteinchannels physically connecting the intracellular space of the cells. In this study, the synchronizationcharacteristics of the cells in the central region were investigated. The characteristics and density of thegap junctions determine the overall electrical conductance coupling the cells. The simulations show thata small number of gap junction is sufficient for synchronisation to occur where the coupled cells share acommon inter beat interval, determined by phase resetting of the pairs. This common value is notconstant, however, but drifts with further increases in coupling conductance.