Threshold Models of Intracellular Calcium Release
Stephen Coombes
Abstract.
Among all the regulators of cellular signalling, Calcium ranks as one
of the most important. In many cell types Calcium signalling is
associated with the generation of waves. In this talk I will present
a bidomain fire-diffuse-fire model that facilitates mathematical
analysis of such propagating waves in living cells. Modelling Calcium
release as a threshold process allows the explicit construction of
travelling wave solutions to probe the dependence of Calcium wave speed
on physiologically important parameters. A linear stability analysis
identifies the newly discovered 'Tango waves' as a dynamic instability
of propagating pulse solutions. Furthermore, I will use the bidomain
model to shed some light on recently discovered sensitisation waves in
ventricular myocytes. Moving next to atrial myocytes, I will describe
the development of a computationally efficient framework to investigate
stochastic Calcium release and propagation in a realistic
three-dimensional cellular geometry.