title: [Ca2+]i-transients and actin polymerization in human neutrophils under stimulation with GRO alpha and complement fragment C5a.
abstract: The neutrophil chemotaxins, complement fragment C5a (C5a) and GRO alpha, induced the mobilization of Ca2+ from intracellular stores and the polymerization of actin in human neutrophils as assayed by flow cytometric measurements. [Ca2+]i-transients developed as an "all-or-none" response. Individual neutrophils required different threshold concentrations of added ligand to induce [Ca2+]i-transients which were then always maximal. In contrast, chemotaxin-induced formation of actin filaments in single neutrophils occurred in a dose-dependent manner. Pertussis toxin blocked chemotaxin-induced actin polymerization and [Ca2+]i-transients indicating that both cell responses shared initial activation steps such as ligand binding and activation of guanine nucleotide-binding proteins (G-proteins).
authors.affiliation: University of Freiburg, Department of Dermatology, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Metzner
authors.forename: J
authors.initials: J
authors.lastname: Elsner
authors.forename: G
authors.initials: G
authors.lastname: Dobos
authors.forename: E
authors.initials: E
authors.lastname: Kownatzki
authors.forename: F
authors.initials: F
authors.lastname: Parlow
authors.forename: I
authors.initials: I
authors.lastname: Schraufstätter
authors.forename: J
authors.initials: J
authors.lastname: Norgauer
mesh_terms: D000199:Actins / Q000096:biosynthesis*; D002118:Calcium / Q000378:metabolism*; D054360:Chemokine CXCL1; D019743:Chemokines, CXC; D002630:Chemotactic Factors / Q000494:pharmacology*; D015936:Complement C5a / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D005434:Flow Cytometry; D019204:GTP-Binding Proteins / Q000378:metabolism; D006133:Growth Substances / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D036341:Intercellular Signaling Peptides and Proteins; D007700:Kinetics; D009504:Neutrophils / Q000187:drug effects / Q000378:metabolism*; D037342:Pertussis Toxin; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
chemical_list: D000199:Actins; C475829:CXCL1 protein, human; D054360:Chemokine CXCL1; D019743:Chemokines, CXC; D002630:Chemotactic Factors; D006133:Growth Substances; D036341:Intercellular Signaling Peptides and Proteins; D010566:Virulence Factors, Bordetella; D015936:Complement C5a; D037342:Pertussis Toxin; D019204:GTP-Binding Proteins; D002118:Calcium