Effects of 5-oxo-eicosanoids on platelet aggregation. (A) The effects of vehicle (veh; 2.5 μL DMSO), 5-oxo-ETE (5o), 5-oxo-12-HETE (cis), and 8-trans-5-oxo-12-HETE (tr) on platelet aggregation induced by a maximally effective concentration of arachidonic acid (AA; 4 μmol/L), added 2 minutes later. The ticks on the bar below the tracings are 1 minute apart. (B) Concentration-response curves for the effects of 5-oxo-ETE (•; 5o-ETE), 5-oxo-12-HETE (○; 5o-12h [cis]), and 8-trans-5-oxo-12-HETE (▪; 5o-12h [tr]) on platelet aggregation induced by the lowest maximally effective concentration of arachidonic acid (2 to 4 μmol/L). All values are means ± SE of determinations on platelets from three different donors.