title: Calcium signaling in mast cells: focusing on L-type calcium channels.
abstract: Mast cells play central roles in adaptive and innate immunity. IgE-dependent stimulation of the high-affinity IgE receptor (FcεRI) results in rapid secretion of various proinflammatory chemical mediators and cytokines. All of the outputs depend to certain degrees on an increase in the intracellular Ca(2+) concentration, and influx of Ca(2+) from the extracellular space is often required for their full activation. There is strong evidence that FcεRI stimulation induces two different modes of Ca(2+) influx, store-operated Ca(2+) entry (SOCE) and non-SOCE, which are activated in response to endoplasmic reticulum Ca(2+) store depletion and independently of Ca(2+) store depletion, respectively, in mast cells. Although Ca(2+) release-activated Ca(2+) channels are the major route of SOCE, recent evidence indicates that they are not the only Ca(2+) channels activated by Ca(2+) store depletion. The recent data suggest that L-type Ca(2+) channels, which were thought to be a characteristic feature of excitable cells, exist in mast cells to mediate non-SOCE, which is critical for protecting mast cells against activation-induced mitochondrial cell death. In this chapter, we provide an overview of recent advances in our understanding of Ca(2+) signaling in mast cells with a special attention to the emerging role for the L-type Ca(2+) channels as a regulator of mast cell survival.
authors.affiliation: Division of Molecular Cell Immunology and Allergology, Nihon University Graduate School of Medical Science, 30-1 Oyaguchikami-cho Itabashi-ku, Tokyo 173-8610, Japan. suzuki.yoshihiro@nihon-u.ac.jp
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Toshio
authors.initials: T
authors.lastname: Inoue
authors.forename: Chisei
authors.initials: C
authors.lastname: Ra
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D020746:Calcium Channels, L-Type / Q000502:physiology*; D020013:Calcium Signaling / Q000502:physiology*; D006801:Humans; D015640:Ion Channel Gating; D008407:Mast Cells / Q000378:metabolism*; D008928:Mitochondria / Q000378:metabolism; D009569:Nitric Oxide / Q000502:physiology; D017455:Receptors, IgE / Q000502:physiology
chemical_list: D020746:Calcium Channels, L-Type; C502447:MS4A2 protein, human; D017455:Receptors, IgE; D009569:Nitric Oxide; D002118:Calcium