title: Two-dimensional model of calcium waves reproduces the patterns observed in Xenopus oocytes.
abstract: Biological excitability enables the rapid transmission of physiological signals over distance. Using confocal fluorescence microscopy, we previously reported circular, planar, and spiral waves of Ca2+ in Xenopus laevis oocytes that annihilated one another upon collision. We present experimental evidence that the excitable process underlying wave propagation depends on Ca2+ diffusion and does not require oscillations in inositol (1,4,5)trisphosphate (IP3) concentration. Extending an existing ordinary differential equation (ODE) model of Ca2+ oscillations to two spatial dimensions, we develop a partial differential equation (PDE) model of Ca2+ excitability. The model assumes that cytosolic Ca2+ couples neighboring Ca2+ release sites. This simple PDE model qualitatively reproduces our experimental observations.
authors.affiliation: Department of Pharmacology, Mayo Clinic and Foundation, Rochester, Minnesota.
authors.forename: S
authors.initials: S
authors.lastname: Girard
authors.forename: A
authors.initials: A
authors.lastname: Lückhoff
authors.forename: J
authors.initials: J
authors.lastname: Lechleiter
authors.forename: J
authors.initials: J
authors.lastname: Sneyd
authors.forename: D
authors.initials: D
authors.lastname: Clapham
mesh_terms: D000818:Animals; D055592:Biophysical Phenomena; D001703:Biophysics; D002118:Calcium / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism; D004058:Diffusion; D005260:Female; D066298:In Vitro Techniques; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism; D008433:Mathematics; D008954:Models, Biological; D009865:Oocytes / Q000378:metabolism*; D014982:Xenopus laevis
chemical_list: D015544:Inositol 1,4,5-Trisphosphate; D002118:Calcium