Pertussis toxin inhibits intracellular pH changes in human neutrophils stimulated by N-formyl-methionyl-leucyl-phenylalanine.
Changes of intracellular pH in human neutrophils were monitored by 9-aminoacridine fluorescence. Both initial acidification and subsequent alkalinization phases induced by a chemotactic peptide, N-formyl-methionyl-leucyl-phenylalanine were dependent on the extracellular Ca2+-concentrations, and a calcium ionophore, A-23187 similarly induced the pH-changes. Pertussis toxin inhibited the pH-changes induced by the peptide while cholera toxin did not. The pH-changes induced by A-23187 were not affected by the toxins. The results suggest that the inhibitory guanine-nucleotide regulatory protein and Ca2+ are involved in the pH-changes induced by the peptide.
D000328:Adult; D000584:Amiloride / Q000494:pharmacology; D001427:Bacterial Toxins / Q000494:pharmacology*; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000494:pharmacology; D004533:Egtazic Acid / Q000494:pharmacology; D019204:GTP-Binding Proteins / Q000502:physiology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology*; D009504:Neutrophils / Q000187:drug effects / Q000502:physiology*; D037342:Pertussis Toxin; D013050:Spectrometry, Fluorescence; D010566:Virulence Factors, Bordetella
D001427:Bacterial Toxins; D010566:Virulence Factors, Bordetella; D000001:Calcimycin; D004533:Egtazic Acid; D009240:N-Formylmethionine Leucyl-Phenylalanine; D000584:Amiloride; D037342:Pertussis Toxin; D019204:GTP-Binding Proteins; D002118:Calcium