title: Observable effects of Ca2+ buffers on local Ca2+ signals.
abstract: Calcium signals participate in a large variety of physiological processes. In many instances, they involve calcium entry through inositol 1,4,5-trisphosphate (IP(3)) receptors (IP(3)Rs), which are usually organized in clusters. Recent high-resolution optical experiments by Smith & Parker have provided new information on Ca(2+) release from clustered IP(3)Rs. In the present paper, we use the model recently introduced by Solovey & Ponce Dawson to determine how the distribution of the number of IP(3)Rs that become open during a localized release event may change by the presence of Ca(2+) buffers, substances that react with Ca(2+), altering its concentration and transport properties. We then discuss how buffer properties could be extracted from the observation of local signals.
authors.affiliation: Laboratory of Mathematical Physics, Rockefeller University, 1230 York Avenue, New York, NY 10065, USA.
authors.forename: Guillermo
authors.initials: G
authors.lastname: Solovey
authors.forename: Silvina
authors.initials: S
authors.lastname: Ponce Dawson
mesh_terms: D000465:Algorithms; D002021:Buffers; D002118:Calcium / Q000737:chemistry*; D020013:Calcium Signaling; D002462:Cell Membrane / Q000502:physiology*; D003198:Computer Simulation; D003600:Cytosol / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004721:Endoplasmic Reticulum / Q000378:metabolism; D015544:Inositol 1,4,5-Trisphosphate / Q000737:chemistry*; D015640:Ion Channel Gating / Q000502:physiology; D007700:Kinetics; D008954:Models, Biological; D015233:Models, Statistical; D011336:Probability
chemical_list: D002021:Buffers; D015544:Inositol 1,4,5-Trisphosphate; D002118:Calcium