低剂量率60Co γ射线和252Cf裂变中子混合照射对大鼠造血及抗氧化系统的影响

摘要

Objective To study the effects of low dose rate 60Co γ ray combined with 252Cf neutron irradiation on hematopoietic and antioxidation systems in rats.Methods Sixteen SD male rats were randomly divided into the irradiation group and the control group,each consisting of 8 rats.The irradiation group was exposed to whole-body 60 Co γray (with daily dose rate of 0.072 Gy) for 1 hour and to 252 Cf neutron (with daily dose rate of 0.085 mGy/h) for 20 hours,for a total of 7 successive days.Peripheral blood cell counts,main organ indices,bone marrow DNA contents,SOD activity and MDA content of rats were monitored,at day 8 after irradiation.Results Compared with those of the control group [(6.2 ± 2.4) × 109/L],WBC of the irradiation group decreased significantly following irradiation [(3.4 ± 1.2) × 109/L],(P ＜ O.05),but no statistical significance could be noted in the changes of various organ indices (P ＞ O.05).Bone marrow DNA contents and serum SOD activity all decreased significantly (P ＜ 0.05),while organ indices and MDA contents seemed to increase,but without statistical significance (P ＞ 0.05).Conclusions 60 Co γirradiation combined with 252Cf neutron irradiation could obviously damage the hemopoietic and anti-oxidation systems of rats.%目的 探讨低剂量率60Co γ射线与252Cf裂变中子混合照射对大鼠的生物效应.方法 16只雄性SD大鼠按数字表法随机分成实验组和对照组,每组8只.实验组每天依次暴露于60Co γ射线1h(剂量率为0.072 Gy/h),252Cf裂变中子20 h(剂量率为0.085 mGy/h),连续7d.照后第8天检测大鼠外周血细胞计数、主要脏器指数、骨髓DNA含量、血清超氧化物歧化酶(SOD)活力及丙二醛(MDA)含量.结果 与对照组[(6.2 ±2.4)×109/L]相比,实验组大鼠外周血白细胞数[(3.4±1.2)×109/L](WBC)显著降低(P＜0.05),各项脏器指数变化组间差异无统计学意义(P＞0.05),骨髓DNA含量显著降低(P＜0.05)；血清SOD活力显著降低(P＜0.05),MDA含量有上升趋势,但差异无统计学意义(P＞0.05).结论 低剂量率60Co γ射线和252Cf裂变中子混合照射对大鼠造血系统及抗氧化系统有一定的损伤作用.