Inhibition of ionophore‐stimulated leukotriene B4 production in human leucocytes by monohydroxy fatty acids

Abstract

Leukotriene B4 (LTB4) release by calcium ionophore‐stimulated human leucocytes was measured by use of selective solvent partition of reaction mixtures and an agarose microdroplet chemokinesis assay, and the inhibitory effects of four monohydroxy fatty acids were determined. 15‐Hydroxy‐eicosatetraenoic acid (15‐HETE) was the most effective inhibitor of LTB4 production with an approximate IC50 value of 6 μM and 99% inhibition at 50 μM, whereas 13‐hydroxyoctadecadienoic acid (13‐HODD) and 12‐HETE were weaker inhibitors with approximate IC50 values of 32 μM and 23 μM, and 59% and 68% inhibition at 50 μM, respectively. We suggest that 13‐HODD and 12‐HETE, which are present in large amounts in the lesions of the skin disease psoriasis, may act as endogenous modulators of 5‐lipoxygenase activity in skin. 1985 British Pharmacological Society