title: trans-Stilbene oxide: an inducer of rat hepatic microsomal and nuclear epoxide hydrase and mixed-function oxidase activities.
abstract: The administration of trans-stilbene oxide to rats resulted in increased hepatic microsomal and nuclear epoxide hydrase (with styrene oxide (SO), benzo[a]pyrene 4,5-oxide (4,5-BP) as substrates) and aryl hydrocarbon hydroxylase (AHH) activities. Hepatic microsomal aminopyrine N-demethylase, benzphetamine N-demethylase, and ethylmorphine N-demethylase activities were also increased. These increases in microsomal enzyme activity were dose- and time-dependent (about 100% at 200 mg/kg body weight, administered for 2 consecutive days). However, only marginal increases in hepatic microsomal NADPH-cytochrome c reductase activity and cytochrome P-450 content were observed. No apparent proliferation of hepatic endoplasmic reticulum occurred in trans-stilbene oxide pretreated rats. The administration of trans-stilbene oxide has no effect on hepatic glutathione S-transferase activities (with SO or 4,5-BPO as substrates). None of the parameters were affected in pulmonary microsomes from treated rats. The in vitro addition of trans-stilbene oxide (10(-6)--10(-2) M) did not affect hepatic epoxide hydrase or glutathione S-transferase activities.
mesh_terms: D000818:Animals; D002467:Cell Nucleus / Q000187:drug effects / Q000201:enzymology; D004790:Enzyme Induction / Q000187:drug effects; D004851:Epoxide Hydrolases / Q000096:biosynthesis*; D005260:Female; D008099:Liver / Q000187:drug effects / Q000201:enzymology* / Q000648:ultrastructure; D008297:Male; D008862:Microsomes, Liver / Q000187:drug effects / Q000201:enzymology; D006899:Mixed Function Oxygenases / Q000096:biosynthesis*; D010088:Oxidoreductases / Q000096:biosynthesis*; D051381:Rats; D012737:Sex Factors; D013267:Stilbenes / Q000494:pharmacology*
chemical_list: D013267:Stilbenes; D006899:Mixed Function Oxygenases; D010088:Oxidoreductases; D004851:Epoxide Hydrolases