ACTIVITIES OF CYTOCHROME P450-DEPENDENT MONOOXYGENASES AND ANTIOXIDANT ENZYMES IN DIFFERENT ORGANS OF NORWAY RATS (RATTUS-NORVEGICUS) INHABITING REFERENCE AND CONTAMINATED SITES

Wild Norway rats (Rattus norvegicus) were collected from a site contam inated by a range of polycyclic aromatic hydrocarbons (PAHs), mineral oils, polychlorobiphenyls (PCBs) and heavy metals. Activities of cytoc hrome P450 monooxygenases (ethoxy-, pentoxy- and benzoxy-resorufin O-d ealkylases, and 4-nitrophenol hydroxylase) were measured in microsomal fractions from liver and lung. Antioxidant enzyme activities (superox ide dismutase, catalase, selenium-dependent and non-selenium-dependent glutathione peroxidases) were also measured in cytosolic fractions fr om lung and liver, and in erythrocytes. The levels of activities were compared with those found in control laboratory rats and in wild Norwa y rats reared in a terrarium. Results show that rats living in a pollu ted environment have monooxygenase activities higher than that of cont rol animals in both liver and lung. Some modifications of antioxidant enzyme activities were also found in these animals.