Effect of Irradiation by X-Rays on the Exhalation of Carbon Dioxide by the Mouse

Abstract

IT has been shown previously that the rate of formation of deoxyribonucleio acid is depressed by a sublethal dose of X-rays. Both the incorporation of phosphorus-32^1–5 and that of carbon-14 ^6,7 was found to be reduced about 50 per cent. The rate of incorporation of carbon-14 into the purines of ribonucleic acid is reduced as well⁷, though to a smaller extent than its incorporation into the purines of deoxyribonucleic acid. These blocking effects are presumably due to in-activation of enzymes involved in the synthesis of the deoxyribonucleic acid and ribonucleic acid compounds. One or a few days after irradiation, the incorporation of carbon-14 into purines of deoxyribonucleic acid has nearly returned to the rate for the non-irradiated controls. This suggests that a partial reactivation has occurred. The early metabolic changes produced by irradiation are not confined to interference with nucleic acid synthesis. We find that irradiation interferes with glucose metabolism as well.