13-Hydroxyoctadecadienoic acid (13-HODE) stimulates prostacyclin production by endothelial cells

The effect of 13-hydroxyoctadecadienoic acid (13-HODE), an endogenous lipoxygenase metabolite of linoleic acid, on prostacyclin production by fetal bovine aortic endothelial cells was evaluated. Time-dependent release of radioimmunoassayable 6KPGF1 alpha in the presence of 13-HODE (10 uM) was stimulated by 39%, 27%, and 34% at 10, 30 and 120 min respectively. 13-HODE (10 uM) had no effect on the conversion of exogenous [14C] arachidonic acid (AA) to prostacyclin. When the effect on AA release was evaluated in [14C] AA prelabeled cells, 13-HODE (10nM) stimulated the release of AA from membrane phospholipids. Analysis of cellular phospholipids revealed a significant decrease in phosphatidylethanolamine. Our results demonstrate that 13-HODE stimulates prostacyclin production by enhancing AA release from phospholipids.