title: Mucus-stimulating factor in tears.
abstract: Mechanisms responsible for regulation of tear film mucus are poorly understood. Humoral factors responsible for stimulation of mucus secretion can be studied in vitro by using the free-swimming urn cell, a normal component of the coelomic fluid of the marine invertebrate Sipunculus nudus. With this system, a tear mucus-stimulating factor was found in normal human tears but was markedly decreased in patients with dry eye syndromes. It is suggested that a mucus-stimulating factor exists in normal human tears and that a decrease in this substance may be instrumental in the pathophysiology of certain dry eye syndromes.
mesh_terms: D000818:Animals; D001681:Biological Assay / Q000379:methods; D002477:Cells / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D007637:Keratoconjunctivitis / Q000503:physiopathology; D046911:Macromolecular Substances; D009093:Mucus / Q000378:metabolism*; D009348:Nematoda / Q000502:physiology; D013666:Tears / Q000032:analysis* / Q000378:metabolism; D014985:Xerophthalmia / Q000503:physiopathology*
chemical_list: D046911:Macromolecular Substances