ABSTRACT
Studies on nitrogen metabolism in rats and dogs during acute radiation damage were made, the main results being shown as follows:1. Rats given 630 r whole body radiation showed marked decrease of food intake, but their body weight losses exceeded substantially those of non-radiated rats in pair feeding group. As compared with the latter, the former had more excretion of urinary nitrogem and negative nitrogen balance in the 1st and 2nd day following the exposure of X-ray.2. Four adult male dogs were selected as experimental animals. After irradiation of 430 r,the daily intake of protein and calories were decreased and correspondingly the excretion of total nitrogen,urea nitrogen and amino nitrogen became increased, especially in the 1st and 2nd day.3. Three groups of dogs were fed to low, moderate and high protein diet respectively. Their nitrogen balance were different but normal, however, after irradiation of 400 r the nitrogen balances in the low protein diet group became negative whereas that in the moderate or high protein diet group in general was slightly positive.