title: Calcium dynamics on a stochastic reaction-diffusion lattice model.
abstract: We study a stochastic reaction-diffusion lattice model for describing the calcium dynamics in the endoplasmic reticulum (ER) membrane. Calcium channels and calcium ions are placed in two interpenetrating square lattices which are connected by calcium release and diffusion. Calcium ions are released from the ER through the channels and they can both remain in the membrane or spontaneously leave the membrane into the cytosol. The state of the channel is modulated by calcium ions: a channel can be open, closed, or inactive. The model is studied by numerical simulations and mean field theory and exhibits a phase transition from an active state to an absorbing state which is the result of the catalytic calcium release. The critical behavior of the model is in the directed percolation universality class.
authors.affiliation: Instituto de Pesquisa e Desenvolvimento, Universidade do Vale do Paraíba, Avenida Shishima Hifumi, 2911 12244-000, São José dos Campos, SP, Brazil.
authors.forename: Nara
authors.initials: N
authors.lastname: Guisoni
authors.forename: Mário J
authors.initials: MJ
authors.lastname: de Oliveira
mesh_terms: D002118:Calcium / Q000737:chemistry / Q000378:metabolism*; D015220:Calcium Channels / Q000737:chemistry / Q000502:physiology*; D020013:Calcium Signaling / Q000502:physiology*; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism*; D003198:Computer Simulation; D004058:Diffusion; D004721:Endoplasmic Reticulum / Q000737:chemistry / Q000378:metabolism*; D015640:Ion Channel Gating / Q000502:physiology*; D008954:Models, Biological; D008956:Models, Chemical; D015233:Models, Statistical; D013269:Stochastic Processes
chemical_list: D015220:Calcium Channels; D002118:Calcium