Epoxidation of Arachidonic Acid and Prostacyclin in the Kidney
The renal epoxygenase has been demonstrated to be an active pathway for the conversion of arachidonic acid (AA) to 11,12-epoxide, 19-hydroxy and 20-hydroxy-eicosatetraenoic acids. The epoxygenase activity was found to be located predominantly in the renal cortex. This renal epoxygenase pathway also transformed PGI2 to a new, previously unreported, metabolite. This metabolite was isolated and identified by radio gas chromatography and gas chromatography-mass spectrometry as 5-hydroxy-6-keto-PGFlα. Its structure was further confirmed by comparison of the mass-spectra to that of the synthetic standard. The formation of 5-hydroxy-6-keto-PGF1α in the kidney suggested epoxidation of prostacyclin via the renal epoxygenase as an alternative pathway of PGI2 metabolism.
KeywordsArachidonic Acid Rabbit Kidney Epoxyeicosatrienoic Acid Cytochrome P450 Enzyme System Dihydroxyeicosatrienoic Acid
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