BALB／c小鼠重度骨髓型急性放射病模型的建立

 目的　建立BALB／c小鼠重度骨髓型急性放射病模型，为重度骨髓型急性放射病的实验研究提供依据。方法　BALB／c小鼠给予60Coγ射线6.0 Gy一次全身照射。观察小鼠照射后一般临床表现、外周血细胞计数、股骨病理组织学及骨髓细胞集落生成情况。结果　小鼠照射后第3天活动量即有不同程度的减少，但均无呕吐、稀便，照射后第11天白细胞降至最低值（基础水平的3.0 %），照射后第28天恢复至基础水平的53.7 %；照射后第14天血小板降至最低值（基础水平的8.1 %），照射后第28天恢复至基础水平的60.4 %；照射后第14天骨髓病理示骨髓腔呈空虚状态，骨髓有核细胞集落培养亦提示粒细胞-巨噬细胞集落形成单位（CFU-GM）、混合集落形成单位（CFU-Mix）明显下降；照射后第28天骨髓病理、CFU-GM及CFU-Mix未完全恢复；照射后2个月全部小鼠存活。结论　6.0 Gy 60Coγ射线一次全身照射BALB／c小鼠可成功构建重度骨髓型急性放射病模型，可用于骨髓型急性放射病的实验研究。

Establishment of an animal model of severe bone marrow type acute radiation sickness in the BALB/c mice

Objective To establish an animal model of severe bone marrow type acute radiation sickness in the BALB/c mice and to provide a good foundation for further investigation of severe bone marrow type acute radiation sickness. Methods BALB/c mice were given 6.0 Gy 60Co γ-rays total body irradiation. The mice were observed twice a day. The changes in body weight, peripheral blood cell counts were recorded once every three days. Histopathological sections of femur were prepared to observe the histomorphological changes. Bone marrow cells were collected to perform colony cultivation on day 1 before irradiation, and 14 d, 28 d after irradiation. Results The mice were less active three days after irradiation, but there were no vomiting and loose stools. The white blood cell counts were dropped to the nadirs （3.0 %） 11 days after irradiation and recovered to 53.7 % on day 28 after irradiation. The platelet counts were dropped to the nadirs （8.1%） 14 days after irradiation and recovered to 60.4 % on day 28 after irradiation. Histopathological section showed that the bone marrow cavity was almost empty on day 14 after irradiation. Semi-solid bone marrow cell culture results also demonstrated that CFU-GM and CFU-Mix were obviously decreased. They were not yet fully recovered on day 28 after irradiation. All mice were still alive two months after irradiation. Conclusion A routine model of severe bone marrow type acute radiation sickness has been successfully established by exposure to 6.0 Gy 60Co γ-rays.