Open AccessJournal Article
Comparative Metabolism of 7,12-Dimethylbenz(a)anthracene in Liver and Mammary Tissue
TLDR
The data illustrate, for the first time, the ability of the mammary tissue to metabolize 7,12-dimethylbenz(a)anthracene.Abstract:
The metabolism of 7,12-dimethylbenz(a)anthracene to hydroxymethyl derivatives differs in hepatic and mammary tissue homogenates. Countercurrent distribution and carrier recrystallization have been shown to be effective additional tools in the identification of 7-hydroxymethyl-12-methylbenz(a)anthracene, 12-hydroxymethyl-7-methylbenz(a)anthracene, and 7,12-dihydroxymethylbenz(a)anthracene. In the hepatic tissue, 7,12-dimethylbenz(a)anthracene is transformed into all three of these metabolites whereas the mammary gland formed only the monohydroxy compounds. Pretreatment of rats with 3-methylcholanthrene induces a marked increase in 7,12-dimethylbenz(a)anthracene-metabolizing enzymes in the liver causing further conversion of the 7-hydroxymethyl-12-methylbenz(a)anthracene, 12-hydroxymethyl-7-methylbenz(a)anthracene, and 7,12-dihydroxy-7,12-dimethylbenz(a)anthracene to more polar components. In contrast, mammary gland caused a diminution but still detectable level of the carcinogenic 7-hydroxymethyl-12-methylbenz(a)anthracene and a noticeable increase in the conversion to 12-hydroxymethyl-7-methylbenz(a)anthracene. The data illustrate, for the first time, the ability of the mammary tissue to metabolize 7,12-dimethylbenz(a)anthracene.read more
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Differentiation of the mammary gland and susceptibility to carcinogenesis
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Biotransformation and bioactivation of 7,12-dimethylbenz[a]anthracene (7,12-DMBA)
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Mixed function oxidase activities in lactating rats and their offspring following dietary exposure to polybrominated biphenyls
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