DT-diaphorase: differential distribution in rabbit kidney and possible protection against quinone toxicity in the inner medulla.

DT-diaphorase, presently regarded as a protective enzyme against quinone toxicity, was found to increase in activity from cortex to inner medulla within the rabbit kidney. The high activity of DT-diaphorase in renal inner medulla would therefore provide effective protection in that region of kidney against toxicity and carcinogenicity of xenobiotics which are either quinones or converted to quinones via prostaglandin H synthase.