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: Inhibitors of polyamine biosynthesis. 4. Effects of alpha-methyl-(+/-)-ornithine and methylglyoxal bis(guanylhydrazone) on growth and polyamine content of L1210 leukemic cells of mice.
    Author: Newton NE, Abdel-Monem MM.
    Journal: J Med Chem; 1977 Feb; 20(2):249-53. PubMed ID: 836495.
    Abstract:
    L1210 leukemic cells of mice were incubated for a period of two generations in the presence of either alpha-methyl-(+/-)-ornithine, an inhibitor of ornithine decarboxylase, or methylglyoxal bis(guanylhydroazone), an inhibitor of S-adenosylmethionine decarboxylase. alpha-Methyl-(+/-)-ornithine produced a 50% decrease in spermidine levels, reduced putrescine to nondetectable levels, and caused a slight increase in spermine levels of the cells. However, DNA content of the cell suspension was not altered by alpha-methyl-(+/-) ornithine. Thus putrescine and 50% of the cellular content of spermidine are not essential for DNA synthesis in these cells. Methylglyoxal bis(guanylhydrazone) produced a large increase inputrescine levels, the same decrease in spermidine levels as did alpha-methyl-(+/-)-ornithine, and approximately a 45% decrease in spermine levels. These changes were accompanied by a large decrease in the DNA content of the cell suspension. Since the two inhibitors caused a similar decrease in spermidine levels, it is unlikely that the inhibition of DNA synthesis by methylglyoxal bis(guanylhydrazone) is a result of a decrease in the cellular levels of spermidine. Rather, it seems likely that methylglyoxal bis(guanylhydrazone) inhibits DNA synthesis through a mechanism other than a decrease in polyamine levels.
    [Abstract] [Full Text] [Related] [New Search]