Objective: To study the protective effect of Naili capsule on60Co γ-ray induced injury and provide an experimental basis for the development of Naili capsule. Method: Male KM mice were divided into model group

the positive drug group (dose 0.98 g·kg-1) and Naili capsule low

medium and high doses (for 1.82

3.64

7.28 g·kg-1) group

ig

for 7 days consecutively. Experiment was divided into two parts: mice were radiated by 8.5 Gy of 60Co γ ray radiation

survival rate of 30 days was observed and the average survival time of mice was calculated; mice were radiated by 6.5 Gy60Co γ ray radiation. Peripheral blood cells

bone marrow nucleated cell count

the role of the index of immune organs

bone marrow histopathology of mice were detected on 7 days after radiation. Result: The 30-day survival rate (improved survival was 37.5%) and the mean survival time(24.88 d) of mice administered Naili capsule (for 3.64 g·kg-1) were all much higher than those of the model group and protection factor was 1.30.White blood cells of mice irradiated were improved (1.34×109/L on 3 days after radiation and 0.89×109/L on 7 days after radiation) and the marrow nucleated cell counts could be increased (5.89×106 in every femur). The damage of bone marrow hematopoietic cells in mice could be reduced. Conclusion: Naili capsule has significant radioprotective effect in mice.