title: Schistosoma mansoni: cercarial eicosanoid production and penetration response inhibited by esculetin and ibuprofen.
abstract: Cercariae of Schistosoma mansoni produce a wide variety of eicosanoids when stimulated by 3.3 mM linoleate. High-performance liquid chromatography indicated that 10(-5) M esculetin dramatically decreased eicosanoid production by cercariae. Ibuprofen (10(-4) M) also decreased eicosanoid production, but to a lesser extent. These results were confirmed by radioimmunoassay using time-dose curves for esculetin and time curves for ibuprofen. The results reported here indicated that, for cercariae, ibuprofen was neither a specific cyclo-oxygenase inhibitor, as has been reported for platelet and endothelial cells, nor was esculetin a specific inhibitor of lipoxygenase, as has been reported for platelets and mastocytoma cells. Rather, both drugs inhibited cyclo-oxygenase and lipoxygenase enzyme systems. Further, the data indicated that two forms of cyclo-oxygenase exist in cercariae (isozymes?), one initiating the conversion of gamma-dihomolinolenate into the 1-series prostaglandins and another acting on arachidonate forming the 2-series prostaglandins. The cyclo-oxygenase acting on arachidonate has a greater sensitivity to both ibuprofen and esculetin than the enzyme acting on gamma-dihomolinolenate. Cercarial lipoxygenases also varied greatly in their sensitivity to ibuprofen.
authors.forename: B
authors.initials: B
authors.lastname: Salafsky
authors.forename: A C
authors.initials: AC
authors.lastname: Fusco
mesh_terms: D000818:Animals; D001091:Arachidonate Lipoxygenases; D001095:Arachidonic Acids / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D016861:Cyclooxygenase Inhibitors; D006893:Hydroxyeicosatetraenoic Acids / Q000096:biosynthesis; D007052:Ibuprofen / Q000494:pharmacology*; D007814:Larva / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D007975:Leukotriene B4 / Q000096:biosynthesis; D019787:Linoleic Acid; D008041:Linoleic Acids / Q000378:metabolism; D016859:Lipoxygenase Inhibitors; D009068:Movement / Q000187:drug effects; D011458:Prostaglandins E / Q000096:biosynthesis; D011863:Radioimmunoassay; D012550:Schistosoma mansoni / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D014468:Umbelliferones / Q000494:pharmacology*
chemical_list: D001095:Arachidonic Acids; D016861:Cyclooxygenase Inhibitors; D006893:Hydroxyeicosatetraenoic Acids; D008041:Linoleic Acids; D016859:Lipoxygenase Inhibitors; D011458:Prostaglandins E; D014468:Umbelliferones; D007975:Leukotriene B4; D019787:Linoleic Acid; D001091:Arachidonate Lipoxygenases; C007628:esculetin; D007052:Ibuprofen