Characterization of effect of N-formyl-methionyl-leucyl-phenylalanine on leukotriene synthesis in human polymorphonuclear leukocytes.
Human polymorphonuclear leukocytes (PMNLs) were exposed to N-formyl-methionyl-leucyl-phenylalanine (f-Met-Leu-Phe) in the presence or absence of exogenous arachidonic acid. Analysis of incubation mixtures by high-performance liquid chromatography showed that f-Met-Leu-Phe stimulated the synthesis of 5-hydroxy-eicosatetraenoic acid (HETE) and of leukotriene B4 (LTB4) which was rapidly metabolized into 20-OH-LTB4 and 20-COOH-LTB4. The stimulatory effect of f-Met-Leu-Phe was dose and time dependent. The tripeptide showed maximum stimulatory activity at the concentration of 1 microM and after 20-30 min of incubation. Addition of arachidonic acid to the f-Met-Leu-Phe-stimulated PMNLs resulted in an increase in the synthesis of LTB4 and 5-HETE. Pretreatment of the PMNLs with cytochalasin B strongly potentiated (up to six-fold) the stimulatory effect of f-Met-Leu-Phe on 5-lipoxygenase product synthesis, whereas cytochalasin B alone or with arachidonic acid had no significant effect. The tripeptide did not increase the synthesis of platelet-derived 12-HETE, and 12-hydroxyheptadecatrienoic acid, or of PMNL-derived 15-HETE, suggesting that its action was selective for PMNL 5-lipoxygenase. The present data indicate that f-Met-Leu-Phe causes the release of arachidonic acid from cellular lipids and activates the 5-lipoxygenase.
Salari
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Braquet
P
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Naccache
P
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Borgeat
P
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D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism; D003571:Cytochalasin B / Q000494:pharmacology; D006801:Humans; D006893:Hydroxyeicosatetraenoic Acids / Q000096:biosynthesis; D007975:Leukotriene B4 / Q000096:biosynthesis*; D008084:Lipoxygenase / Q000378:metabolism; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology*; D009504:Neutrophils / Q000187:drug effects* / Q000378:metabolism
D001095:Arachidonic Acids; D006893:Hydroxyeicosatetraenoic Acids; D007975:Leukotriene B4; D016718:Arachidonic Acid; D003571:Cytochalasin B; C022022:5-hydroxy-6,8,11,14-eicosatetraenoic acid; D009240:N-Formylmethionine Leucyl-Phenylalanine; D008084:Lipoxygenase