title: Peroxidase activity in the rat Zymbal gland and its possible role in the metabolic activation of aminostilbenes in the target tissue.
abstract: Peroxidase (EC 1.11.1.7) activity is detected in the rat Zymbal gland, which is the target organ of trans-4-dimethylaminostilbene (trans-DAS) carcinogenicity. Measurements of peroxidase activity in ovariectomized rats show that the enzyme activity is lowered in the uterus and Zymbal gland by trans-DAS treatment and in the lungs by diethylstilboestrol (DES) treatment. In an in vitro system containing horseradish peroxidase (HRP), hydrogen peroxide and calf-thymus DNA, irreversible binding of the 3H-labelled trans-DAS metabolites 3-hydroxy-, 4'-hydroxy-, and N-hydroxy-4-acetylaminostilbene to DNA is observed. The peroxidase activity in the Zymbal gland together with the HRP-catalyzed oxidation of trans-DAS metabolites suggest a possible role for peroxidase in the organ-specific metabolic activation of trans-DAS.
mesh_terms: D000818:Animals; D001711:Biotransformation; D002273:Carcinogens / Q000378:metabolism*; D002369:Castration; D005260:Female; D008168:Lung / Q000201:enzymology; D010544:Peroxidases / Q000378:metabolism*; D051381:Rats; D012627:Sebaceous Glands / Q000201:enzymology*; D013267:Stilbenes / Q000378:metabolism*
chemical_list: D002273:Carcinogens; D013267:Stilbenes; C016228:4-aminostilbene; D010544:Peroxidases