Arachidonic acid epoxygenase metabolites

P-450 arachidonic acid-derived metabolites have been identified in human urine [189]. The renal cytochrome P-450 system is involved in catalyzing the enzymatic transformation of arachidonic acid. This reaction can involve either an epoxygenase system yielding various epoxides or a mono oxygenase system yielding other oxidation products. Cells of the proximal tubule, thick ascending limb of Henle and the collecting duct contain the major amount of cytochrome P-450 enzyme in the kidney. 

Amruthesh SC, Falck JR, EUis EE. 1992. Brain synthesis and cerebrovascular action of epoxygenase metabolites of arachidonic acid. J Neurochem 58 503-510. 

Fig. 12. Metabolism of arachidonic acid by cytochrome P-450 enzymes and the formation of three structurally distinct metabolite families.

Epoxygenase metabolites of arachidonic acid have potent pharmacological effects on kidney and vascular functions. Particularly well studied is the ability of some of these products to inhibit ion transport, reduce renin activity, and increase water and electrolyte excretion in kidney. Epoxygenase metabolism of arachidonic acid has also been demonstrated in brain,where it could participate in mediating certain intracellular responses of hypothalamic neurons to the modulatory neurotransmitter, dopamine. ... 

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