RESUMO
Objective:To investigate the effect of activation of proteinase activated receptor(PAR)2 on mediator release from mast cells.Methods:P815 cells(a mast cell line) were challenged with various concentrations of PAR-2 agonist peptide,trypsin,tryptase or elasetase with or without PAR-2 antagonist peptide.The supernatants were collected and analyzed by enzyme-linked immunosorbent assay(ELISA) to detect the quantity of released IL-4,IL-6 and histamine.Results:PAR-2 agonist peptide,trypsin or tryptase induced a concentration-dependent IL-4,but not histamine release from P815 mast cells.Trypsin and tryptase induced IL-4 release from the mast cells was blocked by addition of PAR-2 antagonist peptide.No IL-4,IL-6 and histamine release was observed when P815 cells were incubated with elasetase.Conclusion:Induction of IL-4 release from mast cells by trypsin and tryptase through activation of PAR-2 added some novel information on the hypothesis of self-amplification mechanism of mast cell activation.