Linked Life Data

6788991

Source:http://linkedlifedata.com/resource/pubmed/id/6788991

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1981-9-15
pubmed:abstractText
The effect of age and parity on the binding of 7,12-dimethybenz[a]anthracene (DMBA) to DNA and the repair of DMBA-damaged DNA have been demonstrated in logarithmic phase and confluent mammary epithelial cell cultures from young virgin (YV), old virgin (OV), and parous (P) noninbred and inbred Sprague-Dawley rats. Over a dose range of 0.1-0.4 micrograms DMBA/ml, DNA binding was 1.5-to 2.0-fold higher in YV cells than in OV or P cells. In addition, a steeper slope of the dose-response curve was obtained with YV cells, suggesting a greater susceptibility of YV cells to DMBA. Excision repair was determined by measuring, in the presence of hydroxyurea and 5-bromodeoxyuridine, tritiated thymidine incorporation into DNA during the repair process. At high doses od DMBA (0.5-2.0 micrograms/ml), excision repair in YV cells was 1.5 times higher than in OV cells and 2 times higher than in P cells. However, with lower DMBA doses (less than 0.5 micrograms/ml) similar levels of repair were obtained in all 3 groups of rats. Since binding to DNA is higher in YV cells at these low DMBA doses, ti is apparent that OV and P cells exhibit a greater DNA repair per unit damage. These results, therefore, suggest that age and parity not only lower the binding of DMBA to mammary epithelial cell DNA but also increase the efficiency of DNA repair processes, which may explain the lower susceptibility of OV and P rats to DMBA-induced mammary carcinogenesis.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0027-8874
pubmed:author
pubmed:issnType
Print
pubmed:volume
67
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
155-61
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1981
pubmed:articleTitle
7,12-dimethylbenz[a]anthracene-induced DNA binding and repair synthesis in susceptible and nonsusceptible mammary epithelial cells in culture.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't