Probing a reduced equation for intracellular calcium dynamics

Intracellular calcium plays a crucial role in many biological processes. Optical techniques provide a relatively non-invasive method by which calcium signals can be studied. However, obtaining quantitative information on the calcium currents that give rise to a particular image is not straightforward due to the presence of buffers and pumps that affect the calcium dynamics. We have recently developed a novel method to determine the calcium release fluxes that underlie a fluorescent image, which proved to be pretty accurate in both numerically and experimentally generated images (Ventura et al., to be published). The method assumes that a certain number of perturbative terms is enough to capture the way in which the various intracellular processes whose details are unknown affect calcium dynamics. In this paper we investigate the validity of this ansatz using numerical simulations.