低剂量147Pm内照射诱发小鼠细胞遗传突变抗性的研究

目的 研究低剂量^147Pm内污染对红细胞和淋巴细胞遗传突变的影响。方法 应用骨髓和血液嗜多染与正常染红细胞微核检测以及骨髓淋巴细胞染色体畸变分析观察。结果 与正常对照组比较，18．5kBq/g体重^147Pm内污染可引起红细胞微核细胞率和淋巴细胞染色体畸变率明显增多（P＜0．05或0．01）。然而，预先应用0．37、3．7和37Bq/g体重的^147Pm内污染动物，3d后注入18．5kBq/g体重的^147Pm，红细胞微核细胞率以及淋巴细胞染色体畸变率则显著低于单纯高剂量^147Pm组（P＜0．05或0．01）；并且某些细胞突变与对照组比较无显著性差异（P＞0．05）。结论 低剂量^147Pm内污染预处理，可在较长时间内诱导红细胞和淋巴细胞的辐射适应性反应；^147Pm内污染诱导的细胞适应性反应具有较宽的剂量范围；与淋巴细胞染色体畸变比较，嗜多染与正常染红细胞微核亦是较灵敏的辐射生物学指标之一。

Effects of low doses 147Pm internal irradiation against hereditary mutation in mouse cells induced by high dose of radiation

Objective To investigate the effects of low doses 147Pm internal irradiation against hereditary mutation in mouse cells induced by subsequent high dose of 147Pm irradiation. Methods The frequencies of micronucleated polychromatic erythrocytes (mn-PCE) micronucleated normochromatic erythrocytes (mn-NCE) and chromosome aberration in bone marrow and peripheral blood cells were observed. Results The frequencies of nm-PCE、mn-NCE and chromosome aberration induced by high dose of 147Pm irradiation showed a highly significant increase over the control at 24 h after irradiation (P＜0.05 or 0.01).However, the frequencies in cells pre-exposed to 0.37-37 Bq/g of 147Pm were decreased significantly (P＜0.05 or 0.01),as compared with those of the group without pre-exposure. Conclusion Low doses of in vivo 147Pm β-irradiation can induce a radioadaptive response of the lymphocytes and erythroblasts.The induction of the adaptive response has a wide dose range.The mn-PCE and mn-NCE are more sensitive indexes for revealing biological effects of radiation as compared with the chromosome aberration.