Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1998-9-8
pubmed:abstractText
Rat strain variation in hepatic cytochrome P4501A1 (CYP1A1) gene expression caused by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) was investigated along with possible underlying mechanism. TCDD at a single oral dose of 13.5 ng/kg body weight significantly increased hepatic CYP1A1 mRNA expression in DRH, Long-Evans Cinamon (LEC), Long-Evans (LE), and Holtzman (HO) rats, but not in Sprague-Dawley (SD), Wistar-Imamichi (WI), Lewis (LEW), and Fisher-344 (F344) strains. All showed significant induction of CYP1A1 mRNA at a dose of 40 ng/kg, the relative levels decreasing in the order DRH, LEC, HO, LE, F344, WI, LEW, and SD. A more than 35-fold difference in the induction of CYP1A1 RNA was evident between the DRH and SD strains. Based on CYP1A1 induction, classification into two distinctly separate groups was possible, high responders (DRH, LEC, HO, and LE) and low responders (SD, LEW, WI, and F344). The expression levels closely correlated with the steady-state aryl hydrocarbon receptor (AhR) mRNA expression, this being approximately four-fold higher in the high than in the low responder group. Analysis of the aryl hydrocarbon receptor nuclear translocator (ARNT) showed the presence of a wild type as well as an alternately spliced variant in all strains, with a 45-bp deletion whose sequence corresponded to part of 5' end of the basic region of the basic helix-loop-helix domain. Expressed levels of both products were almost equal in all the strains except DRH, LEC and HO, where the wild form predominated. The results suggest that differential expression of both AhR and ARNT are responsible for rat strain-specific differences in TCDD induced CYP1A1 expression.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0006-291X
pubmed:author
pubmed:issnType
Print
pubmed:day
30
pubmed:volume
248
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
554-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:9703964-Amino Acid Sequence, pubmed-meshheading:9703964-Animals, pubmed-meshheading:9703964-Base Sequence, pubmed-meshheading:9703964-Cytochrome P-450 CYP1A1, pubmed-meshheading:9703964-Gene Expression Regulation, Enzymologic, pubmed-meshheading:9703964-Liver, pubmed-meshheading:9703964-Male, pubmed-meshheading:9703964-Molecular Sequence Data, pubmed-meshheading:9703964-Polymerase Chain Reaction, pubmed-meshheading:9703964-RNA, Messenger, pubmed-meshheading:9703964-Rats, pubmed-meshheading:9703964-Rats, Inbred F344, pubmed-meshheading:9703964-Rats, Inbred Lew, pubmed-meshheading:9703964-Rats, Inbred Strains, pubmed-meshheading:9703964-Rats, Sprague-Dawley, pubmed-meshheading:9703964-Rats, Wistar, pubmed-meshheading:9703964-Sensitivity and Specificity, pubmed-meshheading:9703964-Sequence Deletion, pubmed-meshheading:9703964-Species Specificity, pubmed-meshheading:9703964-Tetrachlorodibenzodioxin, pubmed-meshheading:9703964-Transcription, Genetic
pubmed:year
1998
pubmed:articleTitle
Strain differences in cytochrome P4501A1 gene expression caused by 2,3,7,8-tetrachlorodibenzo-p-dioxin in the rat liver: role of the aryl hydrocarbon receptor and its nuclear translocator.
pubmed:affiliation
Chemical Exposure and Health Effects Research Team, National Institute for Environmental Studies, Ibaraki, Japan.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't