Arachidonate 5-Lipoxygenase and Cyclooxygenase Metabolites From Guinea Pig Eosinophils and Macrophages

Abstract

To investigate the cellular sources of arachidonate metabolites during asthma, in vitro productions of thromboxane(TX)B₂, prostaglandin(PG)D₂, leukotriene(LT)B₄ and cysteinyl(Cys)LTs from guinea pig eosinophils and macrophages simultaneously stimulated with the Ca ionophore A23187 were investigated.Eosinophils produced high levels of LTB₄ and TXB₂ and relatively low levels of CysLTs and PGD₂.Although macrophages released abundant TXB₂ and a little PGD₂, 5−lipoxygenase metabolites were below detectable levels.In conclusion, eosinophils produced both cyclooxygenase and 5−lipoxygenase metabolites, while arachidonate metabolism in the macrophages was almost completely inclined toward the cyclooxygenase pathway.