In Vitro: 19(S)-HETE (1 μM; 15 min) dose-dependently induces cAMP in MEG-01 cells with an EC50 value of 520 nM.19(S)-HETE (1 μM-1 M) dose-dependently activates the IP receptor with an EC50 value of 567 nM.19(S)-HETE (10 μM-1 M) displaces 3H-iloprost of IP receptor expressed COS-1 cells with a Ki value of 660 nM.19(S)-HETE (3 μM) relaxes arterial blood vessels and inhibits platelet activation.