Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1993-4-30
pubmed:abstractText
The potential relationship between mutagenesis and carcinogenesis has been examined in the Nagase analbuminemic rat treated with a single dose of benzo[a]pyrene, an incomplete liver carcinogen. The apparent mutation rate at the albumin locus was calculated by determining the number of hepatocytes expressing a cross-reactive product of albumin in analbuminemic rats treated with benzo[a]pyrene. The rate of initiation, the first stage in carcinogenesis, was determined by assessing the number of hepatocytes expressing the placental isozyme of glutathione S-transferase (PGST) after administration of benzo[a]pyrene. Since the expression of PGST may represent hepatocellular changes independent of initiation, promotion with phenobarbital was employed to clonally expand those putatively initiated hepatocytes expressing PGST. With immunohistochemical measures to assess changes in albumin expression, a threefold increase in the number of hepatocytes expressing albumin was detected after administration of benzo[a]pyrene in Nagase analbuminemic rats. A more than five-fold increase in altered hepatic foci (AHF) exhibiting increased PGST expression was observed in animals given benzo[a]pyrene treatment followed by phenobarbital, compared with those given benzo[a]pyrene alone. The number of albumin-expressing single hepatocytes detected was of the same order of magnitude as the number of individual hepatocytes and AHF expressing PGST, suggesting that similar events may be involved in their formation. Since 3 x 10(6) single hepatocytes expressing albumin were found in the analbuminemic rat liver after a single administration of benzo[a]pyrene, while less than 2 x 10(4) AHF expressing PGST were observed, formation of individual hepatocytes expressing albumin was a far more frequent event than clonal expansion of initiated hepatocytes in the Nagase analbuminemic rat. However, the number of loci of PGST expression including AHF and single hepatocytes is comparable to that of single hepatocytes expressing albumin.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0910-5050
pubmed:author
pubmed:issnType
Print
pubmed:volume
84
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
175-83
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Quantitative comparison of initiation and mutation phenotypes in hepatocytes of the analbuminemic rat.
pubmed:affiliation
McArdle Laboratory for Cancer Research, University of Wisconsin Medical School, Madison 53706.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.