Some Effects of X-irradiation on the Metabolism of Deoxyribonucleic Acid in Mammalian Cells Grown in Culture

Abstract

Cultures of strain-L mouse cells were exposed to doses of x-irradiation up to 2300 r. Immediately after treatment the incorporation of ¹⁴C-formate and ³H-thymidine into DNA was depressed, and the degree of this effect was shown to be dependent on oxygen tension. If the cells were allowed to grow for several days after irradiation, mitosis was suppressed, but the synthesis of all constituents, including DNA, continued and resulted in the formation of giant cells.