title: Calcium mobilization in fluoride activated human neutrophils.
abstract: Fluoride ion, at concentrations above 10 mM, was found to elicit a rise in intracellular calcium levels in neutrophils, as monitored by changes in Quin 2 fluorescence intensity. The calcium mobilization response was characterized by a lag period of 4 to 10 min. and a prolonged duration of action (greater than 20 min.). In contrast, the chemotactic peptide, formylmethionyl-leucyl-phenylalanine, induced a rise in intracellular calcium concentrations which peaked within 1 min. Preincubation of the cells with 1 microgram/ml pertussis toxin resulted in inhibition of the formylmethionyl-leucyl-phenylalanine induced response, but not that mediated by fluoride. Recent evidence suggests that the formylmethionyl-leucyl-phenylalanine receptor is coupled to phospholipase C and phosphoinositide degradation through a guanine nucleotide binding protein susceptible to inhibition by pertussis toxin. Present results suggest that fluoride ion may serve to activate this protein in a manner resistant to inhibition by pertussis toxin.
mesh_terms: D000262:Adenylyl Cyclases / Q000097:blood; D002118:Calcium / Q000097:blood*; D005459:Fluorides / Q000494:pharmacology*; D019204:GTP-Binding Proteins / Q000032:analysis; D006801:Humans; D066298:In Vitro Techniques; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000187:drug effects* / Q000378:metabolism; D037342:Pertussis Toxin; D013481:Superoxides / Q000378:metabolism; D013997:Time Factors; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
chemical_list: D010566:Virulence Factors, Bordetella; D013481:Superoxides; D009240:N-Formylmethionine Leucyl-Phenylalanine; D037342:Pertussis Toxin; D019204:GTP-Binding Proteins; D000262:Adenylyl Cyclases; D005459:Fluorides; D002118:Calcium