title: Octachloronaphthalene induction of hepatic microsomal aryl hydrocarbon hydroxylase activity in the immature male rat.
abstract: Administration of octachloronaphthalene to immature male Wistar rats resulted in a dose-dependent increase in several enzymic, electrophoretic and spectral parameters associated with induction of the hepatic microsomal enzymes. Compared to corn-oil (control)treated animals octachloronaphthalene (150 mumol . kg-1) induced hepatic cytochrome P-450 (1.5-fold), benzo [alpha] pyrene hydroxylase (18-fold) and 4-chlorobiphenyl hydroxylase (18-fold) enzyme activities. In addition to increases in the relative peak intensities of the reduced microsomal cytochrome P-450 : CO and ethylisocyanide (EIC) difference spectra the peak maxima were observed at 448.5 and 452.2/428.0 nm, respectively. The effects of administering octachloronaphthalene to the rat were similar to those observed after pretreatment with 3-methylcholanthrene (MC) and electrophoresis of the induced microsomal proteins showed that both compounds enhance heme-staining peptides with comparable electrophoretic mobilities. Moreover coadministration of MC (3 x 100 mumol . kg-1) and octachloronaphthalene (2 x 150 mumol . kg-1) indicated that their inductive effects were not additive. It was concluded that octachloronaphthalene was an MC-type inducer of hepatic microsomal enzymes.
mesh_terms: D000367:Age Factors; D000818:Animals; D001189:Aryl Hydrocarbon Hydroxylases / Q000096:biosynthesis*; D004347:Drug Interactions; D004790:Enzyme Induction / Q000187:drug effects; D006843:Hydrocarbons, Chlorinated / Q000633:toxicity*; D066298:In Vitro Techniques; D008297:Male; D008748:Methylcholanthrene / Q000494:pharmacology; D008862:Microsomes, Liver / Q000187:drug effects* / Q000201:enzymology; D010634:Phenobarbital / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D006843:Hydrocarbons, Chlorinated; D008748:Methylcholanthrene; C032730:octachloronaphthalene; D001189:Aryl Hydrocarbon Hydroxylases; D010634:Phenobarbital