These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Chemical quantification of unscheduled DNA synthesis in cultured hepatocytes as an assay for the rapid screening of potential chemical carcinogens.
    Author: Althaus FR, Lawrence SD, Sattler GL, Longfellow DG, Pitot HC.
    Journal: Cancer Res; 1982 Aug; 42(8):3010-5. PubMed ID: 7093950.
    Abstract:
    Technical modifications of the quantitative determination of unscheduled DNA synthesis in cultured hepatocytes are described which allow for the rapid identification of potentially carcinogenic chemicals on a large-scale screening basis. The test is based on the biochemical quantification of [methyl-3H]thymidine incorporation into DNA in the presence of hydroxyurea following isolation of nuclei from hepatocytes treated with the agent under study. This procedure ("nuclei procedure") eliminates most of the background radioactivity which otherwise obscures the stimulation of DNA repair synthesis by agents that induce a relatively weak response. By combining the nuclei procedure with a double-labeling technique, test results can be obtained within a few hr after exposure of hepatocytes to the test agents. A test series involving 41 agents confirmed the reliability of the nuclei procedure for the assay of DNA repair synthesis. In addition, chemicals which had yielded conflicting results previously in the autoradiographic hepatocyte DNA repair test, such as 4-acetylaminofluorene, or which had passed unrecognized in previous in vitro tests, such as the potent liver carcinogen methapyrilene hydrochloride, scored clearly positive in our test protocol.
    [Abstract] [Full Text] [Related] [New Search]