低剂量率^(60)Coγ射线对SD大鼠的损伤生物效应研究

Effect of Low-dose rate ^(60)Co γ-ray Ionizing Radiation on SD Rats

目的观察低剂量率60Coγ射线对SD大鼠的损伤生物效应,为其防护提供理论依据。方法将SD大鼠置于60Co放射源下照射,每天照射1 h,连续照射7天,剂量率为0.072 Gy/h,累积剂量为0.5 Gy。照射完成后进行相关指标的检测。结果照射后SD大鼠的外周血白细胞为3.50×109/L,对照组为6.2×109/L,下降明显(P<0.05);血小板、红细胞等血常规指标的变化不明显;照射组的骨髓DNA平均OD260吸光值为1.083,对照组的为1.304,骨髓DNA明显降低(P<0.05);照射组血清中SOD活性平均值为373.83 U/ml,对照组为421.59 U/ml,明显下降(P<0.05);与对照组相比,照射组大鼠主要脏器的脏器系数变化不明显。结论低剂量率γ电离辐射对SD大鼠的造血系统、抗氧化系统的损伤较严重,对主要脏器的脏器系数影响不明显。

Objective To study the effect of low - dose rate 60Coγ/ionizing radiation on rats and provide theory foundation for protection of ＂y radiation. Methods SD rats were cumulative exposed to 60Coγ - ray. The expose time was 1 hour for every day and dose rate was 0.072 Gy/h. After 7 days, the accumulated dose reached 0.5 Gy and the associated changes in rats were measured. Results After irradiation, the average number of peripheral white blood cells of rats in experimental group（EG） was 3.50 ×10^9/L, while that of the rats in control group was 6.2×10^9/L. The decrease in EG is siginificant （ P 〈 0.05 ）. Other parameters in blood RT including platelet are of No significant difference. The average value of absorbance at OD260 of DNA in marrow of rats in EG was 1. 083, while that of the rats in control group was 1. 304. The decrease in rats of EG is significant （ P 〈 0.05 ）. The activity of SOD in serum of rats in EG was 373.83 U/ml, while that of the rats in control group was 421.59 U/ml. The decrease in rats of EG is significant （P 〈 0.05 ）. Compared to the rats in control group, the main organ coefficients of rats in EG showed no significant difference. Conclusion Low - dose γ ionizing radiation have severe impairment effect on hematopoietic system and anti - oxidation system. It has no obviously effect on the organ coefficients of the main organs of rats.