Chemotactic peptide-induced arachidonic acid mobilization in human polymorphonuclear leukocytes.

Human polymorphonuclear leukocytes prelabeled with tritiated arachidonic acid liberated radiolabeled products when exposed to the chemotactic peptide fMet-Leu-Phe. The effect was enhanced in the presence of phorbol-12-myristate 13-acetate or 1-oleoyl-2-acetyl glycerol; these agents activate phospholipid- and Ca2+-dependent protein kinase C. In contrast, arachidonic acid mobilization was suppressed by two compounds known to inhibit protein kinase C activity: polymyxin B and 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine. These results suggest that protein kinase C was involved in arachidonic acid mobilization in leukocytes stimulated with chemotactic peptide.