Effects of chlorobenzenes on hepatic porphyrin and drug metabolism in chick embryo and day-old chick
Miranda, C.L.; Wang, J.L.; Henderson, M.C.; Nakaue, H.S.; Buhler, D.R.
Research Communications in Chemical Pathology and Pharmacology 46(1): 13-24
1984
ISSN/ISBN: 0034-5164 PMID: 6505383 Document Number: 229827
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.