Reduction of adrenochrome by rat liver and brain DT-diaphorase.

Liver and brain exhibit DT-diaphorase activity with adrenochrome as a substrate; the latter is an o-quinone derived from the autoxidation of adrenaline exhibiting neurotoxic and cardiotoxic properties. The reaction is strongly inhibited by dicoumarol, a classical inhibitor of DT-diaphorase. DT-diaphorase-reduced adrenochrome undergoes autoxidation as shown by the oxygen uptake occurring during the reaction. It is proposed that, physiologically, DT-diaphorase might exert a protective role by maintaining adrenochrome in its reduced, non-toxic form.