title: Direct demonstration of increased intracellular concentration of free calcium in rabbit and human neutrophils following stimulation by chemotactic factor.
abstract: An increase in the level of intracellular free calcium concentration in rabbit and human neutrophils stimulated by chemotactic factors has been demonstrated directly using the calcium-sensitive fluorescent probe quin-2. Addition of f-Met-Leu-Phe (10(-9) M), C5a (3 x 10(-9) M) or leukotriene B4 (6 x 10(-8) M) to the neutrophils induces a rapid increase in the intracellular concentration of free calcium that reaches a maximum value 15 seconds following stimulation. At concentrations of f-Met-Leu-Phe less than 10(-8) M the enhancement is dose dependent with an ED50 of 8 x 10(-11) M and is significantly reduced in the presence of EGTA in the suspending medium.
mesh_terms: D000634:Aminoquinolines; D000818:Animals; D002118:Calcium / Q000097:blood*; D002634:Chemotaxis, Leukocyte; D003182:Complement C5 / Q000494:pharmacology; D015936:Complement C5a; D006801:Humans; D007975:Leukotriene B4 / Q000494:pharmacology; D009239:N-Formylmethionine / Q000031:analogs & derivatives / Q000494:pharmacology; D009240:N-Formylmethionine Leucyl-Phenylalanine; D009504:Neutrophils / Q000032:analysis* / Q000187:drug effects; D009842:Oligopeptides / Q000494:pharmacology; D011817:Rabbits
chemical_list: D000634:Aminoquinolines; D003182:Complement C5; D009842:Oligopeptides; D007975:Leukotriene B4; D009239:N-Formylmethionine; D009240:N-Formylmethionine Leucyl-Phenylalanine; D015936:Complement C5a; C035738:Quin2-acetoxymethyl ester; D002118:Calcium