title: Calcium signaling in smooth muscle.
abstract: Changes in intracellular Ca(2+) are central to the function of smooth muscle, which lines the walls of all hollow organs. These changes take a variety of forms, from sustained, cell-wide increases to temporally varying, localized changes. The nature of the Ca(2+) signal is a reflection of the source of Ca(2+) (extracellular or intracellular) and the molecular entity responsible for generating it. Depending on the specific channel involved and the detection technology employed, extracellular Ca(2+) entry may be detected optically as graded elevations in intracellular Ca(2+), junctional Ca(2+) transients, Ca(2+) flashes, or Ca(2+) sparklets, whereas release of Ca(2+) from intracellular stores may manifest as Ca(2+) sparks, Ca(2+) puffs, or Ca(2+) waves. These diverse Ca(2+) signals collectively regulate a variety of functions. Some functions, such as contractility, are unique to smooth muscle; others are common to other excitable cells (e.g., modulation of membrane potential) and nonexcitable cells (e.g., regulation of gene expression).
authors.affiliation: Department of Pharmacology, College of Medicine, University of Vermont, Burlington, Vermont 05405, USA.
authors.forename: David C
authors.initials: DC
authors.lastname: Hill-Eubanks
authors.forename: Matthias E
authors.initials: ME
authors.lastname: Werner
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Heppner
authors.forename: Mark T
authors.initials: MT
authors.lastname: Nelson
mesh_terms: D002118:Calcium / Q000378:metabolism*; D020013:Calcium Signaling / Q000502:physiology*; D005786:Gene Expression Regulation / Q000502:physiology*; D008564:Membrane Potentials / Q000502:physiology*; D009119:Muscle Contraction / Q000502:physiology*; D009130:Muscle, Smooth / Q000502:physiology*
chemical_list: D002118:Calcium