不同射线诱发人外周血淋巴细胞微核的剂量-效应关系  

An in vitro Study on Dose Effect Relationship of Micronuclei in Human Peripheral Lymphocytes Induced by Different Radiation Rays

作　　者：肖汉方[1] 朱国英[1] 顾淑珠[1] 陈晓[1] 甘曹辉[1] 

机构地区：[1]复旦大学放射医学研究所,上海200032

出　　处：《环境与职业医学》2011年第5期267-270,276,共5页Journal of Environmental and Occupational Medicine

基　　金：上海市卫生局资助项目(编号:08GWZX0602)

摘　　要：[目的]比较^(60)Coγ射线、X射线和^(137)Csγ射线对人外周血淋巴细胞微核率的影响,并探讨其在低剂量受照者剂量估算中的应用意义。[方法]在0～1.00 Gy的剂量范围内,用^(60)Coγ射线、X射线和^(137)Csγ射线(剂量率分别为0.440、0.073、0.810Gy/min)照射离体人血,采用胞质分裂阻断微核法(cytokinesis-block micronucleus method,CB微核法)培养和制片,计数分析双核CB细胞中微核率和微核细胞率,拟合剂量-效应曲线,并计算不同射线的相对生物效能(relativebiological effectiveness,RBE)。[结果]正常人群中微核自发率很低。采用0.05～1.00 Gy的^(60)Coγ射线、X射线和^(137)Csγ射线照射离体人血后,诱发的淋巴细胞微核率和微核细胞率均随照射剂量增加,二者呈正相关(P<0.01)。采用二次多项式拟合的微核剂量-效应曲线回归方程分别为(?)_1=4.8473+59.3422D+37.3649D^2(^(60)Coγ射线)、(?)_2=1.6209+55.1308D+12.6504D^2(X射线)和Y_3=5.0859+7.5269D+37.2330D^2(^(137)Csγ射线),曲线的拟合指数(R^2)分别为0.9827、0.9948和0.9986,回归系数有统计学意义(P<0.001)。不同类型、不同能量的辐射诱发CB微核的RBE不是单一值,尤其在低剂量辐射照射时RBE值较大。[结论]辐射诱发的淋巴细胞微核与辐射剂量有良好的回归关系,建立的剂量-效应曲线可为低剂量照射的医疗救治和预后评估提供生物剂量估算依据,但需充分考虑辐射类型和辐射能量。[ Objective ] Comparing the differential influence of radiation rays on the micronucleus induction rate in peripheral lymphocyte and estimating the occupational exposure dose. [ Methods ] The in vitro healthy human blood was irradiated at 0-1.00 Gy level with ^60Coγ rays, X rays and ^137Csγ rays respectively（ close rates were 0.440, 0.073 and 0.810 Gy/min respectively ）. After the blood cells were cultured and harvested, the lymphocytes micronuclei were counted through CB mieronuclei method, lymphocyte micronuclei dose-effect curve was constructed, and relative biological effective （ RBE ）values of micronucleus were derived. [ Results ] The spontaneous rate of human lymphocyte micronucleus was very low, but after irradiation with 0.05-1.00 Gy, micronucleus frequency and micronucleus cells frequency increased in a manner correlated to the dose （P 〈 0.01 ）.The regression equations of dose-effect curve of micronuclear were Y2 = 4.847 3 ＋ 59.342 2 D ＋ 37.364 9 D^2 （ ^60Coγ rays ）, 122 = 1.620 9 ＋ 55.130 8 D ＋ 12.650 4 D^2 （ X rays ） and Y 3 = 5.085 9 ＋ 7.526 9 D ＋ 37.233 0 D^2 （ ^137Csγ rays ） respectively. By F test, the regression coefficient of the rate of micronuclei cells and the dose were statistically significantly （ P 〈 0.001 ）. The curve fitting exponents were 0.982 7, 0.994 8 and 0.998 6 respectively. Statistical analysis showed that relative biological effective （ RBE ）values of micronucleus rate, which induced by different kinds of radiation and different energy radiation, were not the same value. [ Conclusion ] A regression equation of doseeffect curve of peripheral lymphocyte micronucleus induced by irradiation was constructed in this laboratory and showed good degree of fitness. It could provide evidence for setting medical remedy plan and evaluating prognosis of the patient with low dose exposure. The kind and energy of radiation should be considered in combined manner.

关 键 词：电离辐射 微核率 剂量-效应关系 微核细胞 

分 类 号：R148[医药卫生—公共卫生与预防医学] TL75[核科学技术—辐射防护及环境保护]