title: Discrete stochastic modeling of calcium channel dynamics.
abstract: We propose a discrete stochastic model for calcium dynamics in living cells. A set of probabilities for the opening/closing of calcium channels is assumed to depend on the calcium concentration. We study this model in one dimension, analytically in the limit of a large number of channels per site N, and numerically for small N. As the number of channels per site is increased, the transition from a nonpropagating region of activity to a propagating one changes from one described by directed percolation to that of deterministic depinning in a spatially discrete system. Also, for a small number of channels a propagating calcium wave can leave behind a novel fluctuation-driven state.
authors.affiliation: Max-Planck Institut für Physik komplexer Systeme, Dresden 01187, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Bär
authors.forename: M
authors.initials: M
authors.lastname: Falcke
authors.forename: H
authors.initials: H
authors.lastname: Levine
authors.forename: L S
authors.initials: LS
authors.lastname: Tsimring
mesh_terms: D015220:Calcium Channels / Q000737:chemistry* / Q000502:physiology*; D015640:Ion Channel Gating / Q000502:physiology*; D008956:Models, Chemical; D011336:Probability; D013269:Stochastic Processes
chemical_list: D015220:Calcium Channels