Biological aspects of cytochrome P450 and associated hydroxylation reactions.

A review is made of the distribution and functions of cytochrome P450 in various tissues. "Normal" levels of the enzyme are tabulated and factors inducing higher levels are discussed. Evidence suggestive of the existence of different species of the enzyme is discussed, as is the hyothesis that genetically defective (or absent) isoenzymes of cytochrome P450 can provide an explanation for the clinical findings caused by the adrenogenital syndrome.