Effects and mechanism of anaphylactoid reaction induced by nonapeptide activating mast cells / 中国药房

ABSTRACT

OBJECTIVE To study the effects and potential mechanism of anaphylactoid reaction induced by nonapeptide IVQKIKHCF activating mast cells. METHODS Using human mast cell line LAD2 as subject， and substance P as positive control， the activation effects of 25， 50 and 100 μmol/L IVQKIKHCF on mast cells were investigated by determining the release rate of β-aminohexosidase， histamine release， and the contents of inflammatory factors； using MrgprX2-knockdown LAD2 cells and Mas- related G protein-coupled receptor X2 （MRGPRX2） high-expression human embryonic kidney cell line HEK293 （MRGPRX2/ HEK293 cells） as subject， the correlation between the activation effect of IVQKIKHCF and MRGPRX2 was investigated by determining the release rate of β-aminohexosidase， and intracellular calcium ion concentration. RESULTS IVQKIKHCF with 25， 50， 100 μmol/L could significantly increase the release rate of β-aminohexosidase and histamine release in LAD2 cells （P＜0.05）， and promote the release of tumor necrosis factor-α， interleukin-8， macrophage inflammatory protein-1β and monocyte chemotactic protein-1 to varying degrees （P＜0.05）. After knocking down MrgprX2， the effects of 25， 50， 100 μmol/L IVQKIKHCF promoting the release of β-aminohexosidase in LAD2 cells were reversed significantly （P＜0.05）， resulting in an increase of calcium ion concentration in MRGPRX2/HEK293 cells. CONCLUSIONS Nonapeptide IVQKIKHCF can promote mast cells to release granular matter and inflammatory mediators by activating MRGPRX2 thus inducing anaphylactoid reaction.