From single channel models to global intracellular calcium signals

G SOLOVEY; D FRAIMAN; B PANDO; S P DAWSON

La Serena

Conferencia; XIV Conference on Nonequilibrium Statistical Mechanics and Nonlinear Physics (MEDYFINOL); 2004

Intracellular IP3-sensitive calcium channels are organized in clusters. A single channel can produce a relatively small calcium signal (blip) but when several channels within a cluster open in a synchronic way larger signals are produced (puffs). In this work we propose a model for such clusters and study statistical properties of puffs: distribution of mean open-times and amplitudes. We compare results obtained using two single channel models which differ in the opening mechanism: one is calcium-dependent and the other calcium-independent. We try to determine which one would better explain the experiments by Ian Parker et al. in  Xenopus oocytes