RESUMO
Guinea pigs were given orally with a daily dose of 0.5 mg ascorbic acid per 100 g body weight 20 days before and 4 days after a whole-body r-irradiation and then injected subcutaneously with 10 mg ascorbic acid at 24 hours intervals. During the injection period, the daily urinary output of total ascorbic acid in the animals irradiated with 500 or 1000 r was significantly higher than that in controls, but the difference of 24 hours excretions of total ascorbic acid between the group irradiated with 150 or 250 r and the control group was not statistically significant.As shown in the urinary output of dehydroascorbic acid and diketo- gulonic acid estimated by our modified Roe's method, r-irradiation has no effect on its excretion in guinea pigs and rats.The levels of ascorbic acid in plasma, spleen and adrenals were significantly lower in the irradiated group than in the control group, but might increase with the increase of the injected dose of ascorbic acid.