γ射线对抗坏血酸代谢的影响

<正> 要判断抗坏血酸对辐射损伤有无效应,首先应该了解电离辐射对机体内抗坏血酸代谢的影响。曾经有许多学者报导电离辐射可使动物的组织与血浆中抗坏血酸含量降低及尿中排出量发生改变。在这些研究中所用的动物均能合成抗坏血酸,因此照射后抗坏血酸代谢的变化尚包括电离辐射对抗坏血酸的生物合成的影响。为了研究电离辐射仅对抗坏血酸代谢的效应,我们采用豚鼠为实验动物,观察γ射线对血浆、脾与肾上腺中抗坏血酸含量与尿中排出量的影响以及不同供给量的抗坏血酸对这些影响的减轻效果。

EFFECT OF r-IRRADIATION ON THE METABOLISM OF ASCORBIC ACID

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.