Peroxynitrite and arachidonic acid. Identification of arachidonate epoxides.

Peroxynitrite is a novel substance capable of oxidation of arachidonic acid. Treatment of [1-14C]arachidonic acid with peroxynitrite at pH 7.4 resulted in formation of a complex mixture of radioactive products. The isolation of these compounds and structural analysis by liquid chromatography/mass spectrometry revealed formation of three epoxyeicosatrienoic acids: 8,9-EET, 11,12-EET and 14,15-EET. These epoxides can play a role in peroxynitrite induced oxidative modification of arachidonic acid in cells.