Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1990-12-24
pubmed:abstractText
P-450 IIC7 and IIIA2 mRNAs are constitutively expressed in the hepatic tissue under developmental control. Both forms--as well as IIIA1, 90% homologous to IIIA2 mRNA--display positive modulation by phenobarbital a prototype inducer of the liver monooxygenases and a strong promoter of experimental chemical hepatocarcinogenesis. In the present work the variations in the concentration of these P-450 mRNA were studied in rats submitted to the hepatocarcinogenic protocol of Solt and Farber. We demonstrate that a decrease in the relative concentrations of P-450 IIC7 and IIIA1, 2 mRNA is set up along the tumor promotion stage. Animals--starting the experimental carcinogenic protocol at pubertal age--show a partial inhibition of the physiological expression of P-450 IIIA1,2 mRNA associated to male sex maturation. Administration of phenobarbital results in an acceleration of the pre-neoplastic process which is concomitant with an induction of P-450 IIC7 as well as IIIA1,2 at the earlier promotion stages. P-450 mRNA concentration markedly decreases as the preneoplastic process develops. While an impaired P-450 IIIA1,2 mRNA relative abundance is observed, an inversion of the modulation of P-450 IIC7 as well as of the male phenotype marker alpha-2u-globulin mRNA arises as the tumor promotion stage progresses, both mRNA becoming repressed in response to phenobarbital.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
23
pubmed:volume
1087
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
157-64
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Modulation of P-450 IIC7 and IIIA1,2 mRNA in pre-neoplastic liver. Effect of promotion by phenobarbital.
pubmed:affiliation
Laboratório de Bioquímica, Instituto Gulbenkian de Ciência, Oeiras, Portugal.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't