title: Calcium signaling in lacrimal glands.
abstract: Lacrimal glands provide the important function of lubricating and protecting the ocular surface. Failure of proper lacrimal gland function results in a number of debilitating dry eye diseases. Lacrimal glands secrete lipids, mucins, proteins, salts and water and these secretions are at least partially regulated by neurotransmitter-mediated cell signaling. The predominant signaling mechanism for lacrimal secretion involves activation of phospholipase C, generation of the Ca(2+)-mobilizing messenger, IP3, and release of Ca(2+) stored in the endoplasmic reticulum. The loss of Ca(2+) from the endoplasmic reticulum then triggers a process known as store-operated Ca(2+) entry, involving a Ca(2+) sensor in the endoplasmic reticulum, STIM1, which activates plasma membrane store-operated channels comprised of Orai subunits. Recent studies with deletions of the channel subunit, Orai1, confirm the important role of SOCE in both fluid and protein secretion in lacrimal glands, both in vivo and in vitro.
authors: Calcium Regulation Group, Laboratory of Signal Transduction, National Institute of Environmental Health Sciences - NIH, Department of Health and Human Services, PO Box 12233, Research Triangle Park, NC 27709, USA. Electronic address: Putney@niehs.nih.gov.
authors: James W
authors: JW
authors: Putney
authors: Calcium Regulation Group, Laboratory of Signal Transduction, National Institute of Environmental Health Sciences - NIH, Department of Health and Human Services, PO Box 12233, Research Triangle Park, NC 27709, USA.
authors: Gary S
authors: GS
authors: Bird
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D015220:Calcium Channels / Q000172:deficiency / Q000235:genetics / Q000378:metabolism; D020013:Calcium Signaling; D004721:Endoplasmic Reticulum / Q000378:metabolism; D006801:Humans; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism; D007765:Lacrimal Apparatus / Q000166:cytology / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism; D009363:Neoplasm Proteins / Q000378:metabolism; D000071737:Stromal Interaction Molecule 1
chemical_list: D015220:Calcium Channels; D008565:Membrane Proteins; D009363:Neoplasm Proteins; C103530:STIM1 protein, human; D000071737:Stromal Interaction Molecule 1; D015544:Inositol 1,4,5-Trisphosphate; D002118:Calcium
keywords: Calcium entry; Calcium oscillations; Calcium release; Calcium signaling; Fluid secretion; IP3; Lacrimal; Orai; Protein secretion; STIM