Developmental pattern of 3-methylcholanthrene-inducible mutagenic activation of N-2-fluorenylacetamide, 2-fluorenamine, and 2,4-diaminoanisole in the rabbit.

The effects of 3-methylcholanthrene (MCA) on mutagenic activation of the carcinogenic arylamines N-2-fluorenylacetamide (FAA), 2-fluorenamine (FA), and 2,4-diaminoanisole (2,4-DAA) by liver homogenates were studied postnatally in Dutch rabbits. These effects were compared with the developmental profiles of cytochrome P448 and aryl hydrocarbon hydroxylase (AHH) activity. Mutagenic activation of FA and 2,4-DAA was increased by MCA as early as 2 days after birth, whereas induction of FAA mutagenicity appeared 6 days after birth. Thereafter, induction of all three arylamines closely paralleled induction of cytochrome P448, which was maintained into adulthood. In contrast, induction of AHH activity by MCA was highest at 2 days of age and decreased to control levels 20 days after birth.