From excitability to oscillations: A case study in vasomotion

One consequence of cell-to-cell communication is the appearance of synchronized behavior, where many cells cooperate to generate new dynamical patterns. We present a simple functional model of vasomotion based on the concept of a two-mode oscillator with dual interactions: via relatively slow diffusive coupling that gives rise to wave dynamics and via fast changes in membrane potential that propagate almost instantly over significant distances. The model reproduces the basic calcium dynamics of the vascular smooth muscle cell: calcium waves which upon increased activity of cGMP-sensitive calcium-dependent chloride channels in the plasma membrane may synchronize into whole-cell oscillations which subsequently may spread across a large population of cells. We show how heterogeneity of the system can induce new patterns.