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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
2
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pubmed:dateCreated |
1990-7-3
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pubmed:abstractText |
Five N-monosubstituted chlorofluoroacetamides have been tested as potential specific irreversible inhibitors of the major phenobarbital-inducible form of rat liver cytochrome P-450 (P450IIB1). In vitro, N-(2-phenethyl)chlorofluoroacetamide was ineffective in causing a time-dependent loss of P450IIB1-mediated androstenedione 16 beta-hydroxylase activity in liver microsomes from phenobarbital-treated rats. However, addition of a nitro or bromo substitutent at the para position of the phenyl group or addition of a second phenyl group at the 1- or 2-position on the phenethyl side chain yielded compounds that caused a selective time-dependent decrease in androstenedione 16 beta-hydroxylase activity relative to four other P-450 form-specific androstenedione or progesterone hydroxylase activities monitored. The two compounds that were the most effective in inactivating P450IIB1 in vitro, N-(2-p-bromophenethyl) and N-(2-p-nitrophenethyl)chlorofluoroacetamide were also administered ip to phenobarbital-treated rats, and inhibition of cytochromes P-450 was assessed by in vitro assays of steroid and R- and S-warfarin hydroxylation in subsequently prepared hepatic microsomes. Both compounds selectively inhibited P450IIB1, and at a dose (200 mg/kg) of N-(2-p-nitrophenethyl)chlorofluoroacetamide that reduced androstenedione 16 beta-hydroxylase activity to approximately one-third of the control level, only two other activities, both attributable to P450IIB1, were decreased. In contrast, steroid and warfarin hydroxylase activities indicative of at least five other cytochromes P-450 were unaffected by the compound. These results indicate the feasibility of an empirical approach to the design of specific cytochrome P-450 inactivators.
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pubmed:grant | |
pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Acetamides,
http://linkedlifedata.com/resource/pubmed/chemical/Cytochrome P-450 Enzyme System,
http://linkedlifedata.com/resource/pubmed/chemical/Hydrocarbons, Halogenated,
http://linkedlifedata.com/resource/pubmed/chemical/Phenobarbital,
http://linkedlifedata.com/resource/pubmed/chemical/Steroid Hydroxylases,
http://linkedlifedata.com/resource/pubmed/chemical/Warfarin
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pubmed:status |
MEDLINE
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pubmed:issn |
0090-9556
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
18
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
168-74
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pubmed:dateRevised |
2007-11-14
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pubmed:meshHeading |
pubmed-meshheading:1971568-Acetamides,
pubmed-meshheading:1971568-Animals,
pubmed-meshheading:1971568-Cytochrome P-450 Enzyme System,
pubmed-meshheading:1971568-Enzyme Induction,
pubmed-meshheading:1971568-Hydrocarbons, Halogenated,
pubmed-meshheading:1971568-Liver,
pubmed-meshheading:1971568-Male,
pubmed-meshheading:1971568-Phenobarbital,
pubmed-meshheading:1971568-Rats,
pubmed-meshheading:1971568-Rats, Inbred Strains,
pubmed-meshheading:1971568-Steroid Hydroxylases,
pubmed-meshheading:1971568-Warfarin
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pubmed:articleTitle |
Selective inactivation by chlorofluoroacetamides of the major phenobarbital-inducible form(s) of rat liver cytochrome P-450.
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pubmed:affiliation |
Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson 85721.
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pubmed:publicationType |
Journal Article,
In Vitro,
Research Support, U.S. Gov't, P.H.S.
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