[Decrease in the tissue-specific resistance of gastric epithelium to acute cell death following inhibition of DNA...

Administration to mice of hydroxyurea caused an acute death of an insignificant number of DNA-synthesizing cells in the epithelium of the glandular stomach. When actinomycin D was injected 8 hours prior to hydroxyurea there occurred a sharp intensification of cell degeneration: about 80% of the cells which synthesized DNA during the hydroxyurea administration proved to degenerate. No intensifying action was produced when actinomycin D was injected simultaneously with hydroxyruea. It is supposed that actinomycin D intensified the protein synthesis in the cells of the stomach (the "superinduction" effect), this increasing their sensitivity to the inhibition of the DNA synthesis.