Research of the Model of Low Dose Radiation-injured Mice

Objective: To study low dose radiation-injured mice model and select sensitive indexe.Methods: The mice were divided into seven groups,one was the control group and the rest six groups irradiated by XHA600 linear accelerator were experimental groups.2,4,8,16hours after the irradiation,part of experimental groups were measured to test the content of blood cells,such as red blood cells(RBC),white blood cells(WBC),platelets(PLT) and hemoglobins(HGB).The weight of liver,spleen and superoxide dismutase(SOD),maleic dialdehyde(MDA) in the organs of these groups had been measured too.The bone marrow biopsy of remaining mice were observed after four weeks.Results: The group exposed in radiation(cumulative dose of 0.4 Gy) had significant decrease in the content of WBC and HGB;the content of RBC decreased too.On the contrary,the content of PLT in this group increased significantly;the weight of liver and spleen in this group decreased significantly;MDA content in liver tissue increased significantly;SOD activity in liver decreased significantly.After 4 weeks,the pathological changes of mice bone marrow cells were associated with the amount of single dosage.What's more,a large single dose(eg,0.6Gy) radiation had greater impact on bone marrow cells,and those cells could not restore themselves during the observation period(4 weeks),however,the cumulative groups had little pathological changes in bone marrow cells.Conclusion: The best low dose radiation-injured mice model is 0.4Gy of cumulative radiation dose group.