title: Effects of chlorobenzenes on hepatic porphyrin and drug metabolism in chick embryo and day-old chick.
abstract: Administration of monochlorobenzene (MCB), p-dichlorobenzene (DCB), or 1,2,4-trichlorobenzene (TCB) at single doses of 800 mg/kg produced an increase in the total porphyrin content of liver of day-old chicks. Porphyrinogenic activity was higher in DCB- and TCB-treated chicks than in MCB-treated chicks. Administration of any of these compounds to chick embryos (40 mg/egg) failed to produce an induction of liver porphyrins. TCB enhanced the excretion of porphyrin in bile of chicks but not of chick embryos. In day-old chicks TCB increased hepatic cytochrome P-450 levels and the activity of 7-ethoxyresorufin deethylase. However, 7-ethoxycoumarin deethylase activity was decreased while cytosolic glutathione S-transferase activity was unchanged. These results point out the differential response of chick embryos and day-old chicks to chlorobenzene-induced changes in porphyrin metabolism as well as the differential induction of microsomal monooxygenases in chicks by TCB.
mesh_terms: D000818:Animals; D000831:Animals, Newborn / Q000378:metabolism; D002642:Chick Embryo; D002645:Chickens; D002722:Chlorobenzenes / Q000633:toxicity*; D008099:Liver / Q000187:drug effects* / Q000378:metabolism; D004364:Pharmaceutical Preparations / Q000378:metabolism*; D011166:Porphyrins / Q000032:analysis*
chemical_list: D002722:Chlorobenzenes; D004364:Pharmaceutical Preparations; D011166:Porphyrins