title: Calcium oscillations and waves in cells.
abstract: From beginning of the life to final moment of the life, Ca(2+) functions as an important signaling messenger. The intracellular Ca(2+) concentration, [Ca(2+)](i), in resting cells is normally maintained at around 100 nM with a very steep ∼20,000 times concentration gradient of Ca(2+) between extracellular and intracellular compartments. Ca(2+) signals in the form of time-dependent changes in [Ca(2+)](i) appear as brief spikes that are organized into regenerative Ca(2+) waves. The release of Ca(2+) from internal stores plays a key role in regulating such Ca(2+) signals. Since global Ca(2+) oscillations arise from Ca(2+) waves initiated locally, it results in generation of stochastic Ca(2+) oscillations. In addition, the hierarchical organization of signaling structures translate the molecular fluctuations of single channels to the whole cell leading to formation of stochastic media. Several recent observations indicate that [Ca(2+)](i) changes are fluctuation driven as opposed to a typical deterministic intracellular reaction-diffusion system model. Elucidation of this signaling mechanism can provide detailed knowledge of relationship between cell signaling and cell physiology of living systems.
authors.affiliation: Department of Environmental and Occupational Health, Robert Stempel College of Public Health and Social Work, Florida International University, 11200 SW 8th Street, HLS-594, Miami, FL 33199, USA. parkashj@fiu.edu
authors.forename: Jai
authors.initials: J
authors.lastname: Parkash
authors.forename: Kamlesh
authors.initials: K
authors.lastname: Asotra
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism*; D020013:Calcium Signaling / Q000502:physiology*; D006801:Humans; D053496:Inositol 1,4,5-Trisphosphate Receptors / Q000502:physiology
chemical_list: D053496:Inositol 1,4,5-Trisphosphate Receptors; D002118:Calcium