title: Requirement of free arachidonic acid for leukotriene B4 biosynthesis by 12-hydroperoxyeicosatetraenoic acid-stimulated neutrophils.
abstract: Stimulation of human neutrophils with 12-hydroperoxyeicosatetraenoic acid (12-HPETE) led to formation of 5S, 12S-dihydroxyeicosatetraenoic acid (DiHETE), but leukotriene B4 (LTB4) or 5-hydroxyeicosatetraenoic acid (5-HETE) was not detectable by reversed-phase high-performance liquid chromatography analysis. N-formylmethionylleucylphenylalanine (FMLP) induced the additional synthesis of small amounts of LTB4 in 12-HPETE-stimulated neutrophils. The addition of arachidonic acid greatly increased the synthesis of LTB4 and 5-HETE by neutrophils incubated with 12-HPETE. In experiments using [1-14C]arachidonate-labeled neutrophils, little radioactivity was released by 12-HPETE alone or by 12-HPETE plus FMLP, while several radiolabeled compounds, including LTB4 and 5-HETE, were released by A23187. These findings demonstrate that LTB4 biosynthesis by 12-HPETE-stimulated neutrophils requires free arachidonic acid which may be endogenous or exogenous.
mesh_terms: D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism* / Q000494:pharmacology*; D000001:Calcimycin / Q000494:pharmacology; D002250:Carbon Radioisotopes; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D006801:Humans; D007700:Kinetics; D007975:Leukotriene B4 / Q000096:biosynthesis*; D015289:Leukotrienes; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000187:drug effects / Q000378:metabolism*
chemical_list: D001095:Arachidonic Acids; D002250:Carbon Radioisotopes; D015289:Leukotrienes; D007975:Leukotriene B4; D016718:Arachidonic Acid; D000001:Calcimycin; D009240:N-Formylmethionine Leucyl-Phenylalanine; C021201:12-HPETE