Distribution and sub-cellular localization of drug metabolizing enzymes in the skin.

The distribution and sub-cellular localization of cytochrome P-450-dependent mono-oxygenase activity in the skin of adult hairless mice has been investigated using ethoxycoumarin, ethoxyresorufin and benzpyrene as substrates. Highest levels of mono-oxygenase activity per unit area of skin were found in the dermis, both before and after induction with benzanthracene. Subcellularly, mono-oxygenase activity was predominantly microsomal and, prior to induction, located entirely in the smooth microsomal fraction.