title: [Calcium ionophore induced histamine and tryptase release from human mast cells].
abstract: OBJECTIVE
  To examine the ability of calcium ionophore (CI) to induce tryptase and histamine release from human mast cells and its mechanisms.
  
  
  METHODS
  Enzymatically dispersed cells from human colons were challenged with CI, and the cell supernatants after challenge were collected. Tryptase release was determined with a sandwich ELISA procedure and histamine release was measured using a glass fibre-based fluorometric assay.
  
  
  RESULTS
  CI was able to induce a concentration dependent release of histamine and tryptase from human colon mast cells following 15 min incubation. The maximum of induced histamine and tryptase release were approximately 5.3 and 2.8 fold more than the levels of spontaneous release, respectively. CI at the concentrations higher than 1.0 micromol/L was able to induce significantly more histamine than tryptase release from mast cells. The time course revealed that the action of CI on mast cells started from 10 s, peaked at 6 min and lasted at least 15 min following incubation. Pertussis toxin and metabolic inhibitors were able to inhibit mast cell response to CI.
  
  
  CONCLUSIONS
  Human colon mast cells were able to release tryptase and histamine in response to CI. The process seemed to be associated with the activation of a G-protein coupled receptor on the membrane of mast cells and requires cell energy supply.
authors.affiliation: Allergy and Inflammation Research Institute, Shantou University Medical College, Shantou 515031, China.
authors.forename: Shao-heng
authors.initials: SH
authors.lastname: He
authors.forename: Yong-song
authors.initials: YS
authors.lastname: He
authors.forename: Hua
authors.initials: H
authors.lastname: Xie
mesh_terms: D061207:Calcium Ionophores / Q000494:pharmacology*; D002478:Cells, Cultured; D003106:Colon / Q000166:cytology; D006632:Histamine / Q000378:metabolism; D006801:Humans; D008407:Mast Cells / Q000187:drug effects* / Q000378:metabolism*; D053802:Tryptases / Q000378:metabolism
chemical_list: D061207:Calcium Ionophores; D006632:Histamine; D053802:Tryptases