Aryl hydrocarbon hydroxylase in mouse mammary gland

The specific activity of aryl hydrocarbon hydroxylase in the mammary gland has been measured in six different mouse strains comprising both mammary cancer susceptibility and resistance, under basal conditions, and after pretreatment of the mice with 3-methylcholanthrene (3MC). No correlation was observed between the ease of 3MC-enhanced mammary tumorigenesis and the basal or induced specific activity of aryl hydrocarbon hydroxylase. Furthermore, it was shown that in the AKR/J and A+/Ki mice, only minor enhancement in aryl hydrocarbon hydroxylase was seen upon injection of 3MC. The C57BL/6J and C3Hf/He Tex mammary glands responded the most in this regard. It was also shown that the inability of the AKR/J or A+/Ki mice to respond was not due to their inability to absorb 3MC from the peritoneal cavity and transmit the polycyclic hydrocarbon to the mammary gland.