title: Comparison of arachidonic acid metabolism in nasal polyps and eosinophils.
abstract: Nasal polyp tissue is characterized by its frequent infiltration by large numbers of eosinophils. We have studied the metabolism of 14C-labeled arachidonic acid by both nasal polyp tissue and by eosinophils. The major metabolite produced by both is 15-hydroxyeicosatetraenoic acid (HETE) with lesser amounts of 12-HETE. No cyclooxygenase pathway products were found. The 15-lipoxygenase activity of nasal polyps averages 30 times that of normal nasal mucosa or chronically inflamed sinus mucosa. Nasal polyps which contained significant numbers of eosinophils averaged 7 times the 15-lipoxygenase activity of nasal polyps without eosinophilia. Thus, eosinophils appear to be a major source of 15-lipoxygenase activity in nasal polyps.
mesh_terms: D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000097:blood / Q000378:metabolism*; D004804:Eosinophils / Q000378:metabolism*; D006801:Humans; D006893:Hydroxyeicosatetraenoic Acids / Q000378:metabolism; D009298:Nasal Polyps / Q000378:metabolism*
chemical_list: D001095:Arachidonic Acids; D006893:Hydroxyeicosatetraenoic Acids; D016718:Arachidonic Acid; C025984:15-hydroxy-5,8,11,13-eicosatetraenoic acid