Human chymase stimulates Ca2+ signaling in human polymorphonuclear cells.
Human chymase is known to function as a chemoattractant for human leukocytes. To investigate the mechanism of the chymase-induced cell migration, change in intracellular calcium concentration ([Ca(2+)]i) was examined in human polymorphonuclear (PMN) cells using Fluo-3 as a fluorescent Ca(2+) indicator. Treatment of PMN cells with human chymase caused [Ca(2+)]i elevation in a concentration-dependent manner. Depletion of extracellular Ca(2+) from the medium partially attenuated the chymase-induced [Ca(2+)]i increase, showing that both Ca(2+) influx and Ca(2+) release from internal stores might be involved in the [Ca(2+)]i response. Pretreatment of the cells with pertussis toxin completely blocked the chymase-induced [Ca(2+)]i signal, suggesting an involvement of G protein in the chymase-mediated [Ca(2+)]i elevation. The data in the present study raise the possibility that the chymase-induced cell migration is mediated by the [Ca(2+)]i elevation, which might be caused by stimulation of a G-protein-coupled receptor such as protease-activated receptors (PARs).
Saito
Kayo
K
Suntory Biomedical Research Limited, 1-1-1 Wakayamadai, Shimamoto-cho, Mishima-gun, 618-8503, Osaka, Japan.
Muto
Tsuyoshi
T
Tomimori
Yoshiaki
Y
Maruoka
Hiroshi
H
Tanaka
Taisaku
T
Fukuda
Yoshiaki
Y
D002118:Calcium / Q000378:metabolism*; D020013:Calcium Signaling / Q000187:drug effects / Q000502:physiology*; D053818:Chymases; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D009504:Neutrophils / Q000187:drug effects / Q000378:metabolism*; D037342:Pertussis Toxin / Q000494:pharmacology; D012697:Serine Endopeptidases / Q000187:drug effects / Q000378:metabolism*
D004791:Enzyme Inhibitors; D037342:Pertussis Toxin; D012697:Serine Endopeptidases; D053818:Chymases; D002118:Calcium