[Increased hepatic aryl 4-monoxygenase in chickens caused by lipophilic xenobiotics].

Hens were treated with three types of lipophil xenobiotics - polychlorinated biphenyl (PCB), lindane and hexachlorobenzene (HCB) - to study changes in the levels of microsomal proteins and in the activity of microsomal aryl 4-monooxygenase in liver. The above foreign substances were given in feed at a dose of 50 mg per kg during a fortnight. The level of microsomal proteins in liver increased after seven-day administration of xenobiotics and was always higher in the course of the experiment than in the controls. The activity of the microsomal enzyme (aryl 4-monooxygenase) was significantly higher in treated hens after seven- and 14-day interval, and also seven days after the end of feeding the contaminated feed mixture. Inductive properties were strongest in polychlorinated biphenyl (Delor 103), but lindane and hexachlorobenzene also induced a statistically significant rise, in comparison with the controls. It is shown that the inductive ability of lipophil xenobiotics is stronger in hens than in chicks, which may influence the metabolism of some biologically important substances in poultry organism.