Evolution of Intracellular Ca~(2+) Waves from about 10,000 RyR Clusters: Towards Solving a Computationally Daunting Task

摘要

Detailed knowledge of spatial-temporal behaviours of intracellular calcium dynamics is very important in understanding excitation-contraction coupling of cardiac myocytes under both normal and pathological conditions, such as initiation and propagation of spontaneous calcium waves. A full cell simulation integrating about 10,000 Ca~(2+) release units (CRUs) in a typical cardiac myocytc is considered a multi-scale, computationally demanding problem. In this paper, we imported an experimentally obtained spatial distribution of Ryanodine Receptor (RyR) clusters into a spatially extended, stochastic model of intracellular Ca~(2+) dynamics, to investigate the role of the structural bifurcation of Z-disks on the initiation and propagation of intracellular Ca~(2+) waves from spatially symmetric Ca~(2+) sparks. Besides, we also proposed a simple parallelization strategy to increase computational speed for this chanllenging problem in cardiac modelling.