Linked Life Data

11370663

Source:http://linkedlifedata.com/resource/pubmed/id/11370663

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2001-5-23
pubmed:abstractText
While fresh human hepatocyte cultures are widely used to model hepatic cytochrome P450 (CYP) regulation and activity, their CYP1A subfamily composition induced by, e.g., polycyclic aromatic hydrocarbons is ambiguous. CYP1A1, CYP1A2, or both have been reported to be expressed, and their varied roles in chemical carcinogenesis makes resolution of which CYPs are expressed essential. We have used an immunoblot system with Bis-Tris-HCl-buffered polyacrylamide gel, which clearly resolves human CYP1A1 and CYP1A2, and polyclonal goat anti-human CYP1A1/CYP1A2 and rabbit anti-human CYP1A2 antibodies to probe the expressed CYP1A1 and CYP1A2 composition of seven individual human hepatocyte cultures induced with 5 microM benzo[k]fluoranthene (BKF) for 24 h. In six of the cultures only CYP1A1 was detected, and in the seventh both CYPs were detected. In most vehicle-treated hepatocyte cultures, neither CYP1A1 nor CYP1A2 was detected. In three additional hepatocyte cultures treated individually with BKF and 2,3,7,8,-tetrachlorodibenzo-p-dioxin (TCDD), the resultant induced CYP1A1/1A2 profiles were essentially not influenced by the nature of the inducing agents. To develop an activity-based assay to differentiate between CYP1A1 and CYP1A2 expression in human hepatocytes, our previously published R warfarin assay (Drug Metab. Disp. (1995) 23, 1339-1345) was applied to TCDD (10 nM)-treated hepatocyte culture. The low concentration of TCDD did not produce inhibition of the warfarin metabolism-such inhibition could confound the results. Based on the ratios of 6- to 8-hydroxywarfarin formed in two cultures, the ratios of CYP1A1/CYP1A2 expressed in these cultures were determined and they agreed with the ratios determined by immunoblot analysis. Thus each individual human hepatocyte culture must be characterized for induced CYP1A1 and CYP1A2 expression in studies of CYP1A activity. The warfarin assay provides a means of characterizing the cultures.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0003-9861
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
389
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
130-4
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:11370663-Adolescent, pubmed-meshheading:11370663-Adult, pubmed-meshheading:11370663-Aged, pubmed-meshheading:11370663-Antibody Specificity, pubmed-meshheading:11370663-Cells, Cultured, pubmed-meshheading:11370663-Child, Preschool, pubmed-meshheading:11370663-Cytochrome P-450 CYP1A1, pubmed-meshheading:11370663-Cytochrome P-450 CYP1A2, pubmed-meshheading:11370663-Enzyme Induction, pubmed-meshheading:11370663-Female, pubmed-meshheading:11370663-Fluorenes, pubmed-meshheading:11370663-Genetic Variation, pubmed-meshheading:11370663-Hepatocytes, pubmed-meshheading:11370663-Humans, pubmed-meshheading:11370663-Immunoblotting, pubmed-meshheading:11370663-Male, pubmed-meshheading:11370663-Middle Aged, pubmed-meshheading:11370663-Stereoisomerism, pubmed-meshheading:11370663-Tetrachlorodibenzodioxin, pubmed-meshheading:11370663-Warfarin
pubmed:year
2001
pubmed:articleTitle
Induction of CYP1A by benzo[k]fluoranthene in human hepatocytes: CYP1A1 or CYP1A2?
pubmed:affiliation
New York State Department of Health, Wadsworth Center, Albany 12201-0509, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.