Modeling 3D Calcium Waves from Stochastic Calcium Sparks in a Sarcomere Using COMSOL Multiphysics®

L. T. Izu[1], Z. Coulibaly[2], B. Peercy[2]
[1]University of California-Davis, Davis, CA, USA
[2]University of Maryland, Catonsville, MD, USA

This paper utilizes the COMSOL Multiphysics® general form PDE interface and MATLAB® to model stochastic calcium waves in a sarcomere (basic unit of a heart cell). The model we present here shows the evolution of waves generated from calcium being released stochastically from sites modeled as point sources. The release sites are distributed on z-disc (planes) in a hexagonal pattern, and their opening allows calcium to diffuse and interact with different species of buffers. The release sites are sensitive to calcium levels and after opening and releasing calcium, undergo a refractory period during which they stay closed. The simulations obtained over a sarcomere domain shows individual stochastic releases of calcium self-organizing into propagating waves.