Intercellular calcium waves in glial cells with bistable dynamics

A two-dimensional model is proposed for intercellular calcium (Ca(2 +)) waves with Ca(2 +)-induced IP(3) regeneration and the diffusion of IP(3) through gap junctions. Many experimental observations in glial cells, i.e. responding to local mechanical stimulation, glutamate application, mechanical stimulation followed by ACh application, and glutamate followed by mechanical stimulation, are reproduced and classified by the model. We show that a glial cell model with bistable dynamics, i.e. a Ca(2 +) oscillation state coexisting with a fixed point, can cause a prolonged plateau of Ca(2 +) signals in the cells nearby the stimulated cell when the cell network responds to the local mechanical stimulation.