Modulation by superoxide anions of neutrophil-mediated platelet activation.
When polymorphonuclear neutrophil-platelet suspensions were stimulated by 0.5 microM N-formyl-Met-Leu-Phe in the presence of 40 U/mL of superoxide dismutase, a significant reduction of platelet secretion was observed (51.4 +/- 6.3% vs 62.4 +/- 4.6% for control; mean +/- SEM; N = 6; P < 0.01). This was due to the superoxide anion scavenging property of superoxide dismutase since neutrophil degranulation, cathepsin G and elastase enzymatic activities (the two main mediators of this cell-to-cell interaction) and platelet reactivity were not affected. Involvement of superoxide anions was confirmed using leukotriene B4, a neutrophil agonist which induces degranulation with minimal superoxide anion production. Indeed, serotonin release induced by this agonist was unchanged whether superoxide dismutase was added or not.
Renesto
P
P
Unité de Pharmacologie Cellulaire, Unité associée Institut Pasteur/INSERM 285, Paris, France.
Si Tahar
M
M
Chignard
M
M
D056649:Cathepsin G; D002403:Cathepsins / Q000032:analysis; D002478:Cells, Cultured; D005966:Glucuronidase / Q000032:analysis; D006801:Humans; D007975:Leukotriene B4 / Q000494:pharmacology; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000187:drug effects* / Q000502:physiology; D010196:Pancreatic Elastase / Q000032:analysis; D015539:Platelet Activation / Q000187:drug effects*; D012697:Serine Endopeptidases; D012701:Serotonin / Q000032:analysis; D013482:Superoxide Dismutase / Q000494:pharmacology*; D013481:Superoxides / Q000032:analysis
D013481:Superoxides; D007975:Leukotriene B4; D012701:Serotonin; D009240:N-Formylmethionine Leucyl-Phenylalanine; D013482:Superoxide Dismutase; D005966:Glucuronidase; D002403:Cathepsins; D012697:Serine Endopeptidases; C534094:CTSG protein, human; D056649:Cathepsin G; D010196:Pancreatic Elastase