Abstract: Objective To explore the effects of different irradiation dosages of X-rays on mouse immune organs. Methods Totally 192 mouse were randomly divided into 6 groups: the normal control group and single irradiation 2.0 Gy group, 3.0 Gy group, 4.0 Gy group, 5.0 Gy group and 6.0 Gy group. The samples were taken respectively from mouse of each group at 24 h, 48 h, 96 h, 192 h after irradiation,and the thymus glands and spleens were weighed and taken for calculating organ index and determining the content of superoxide dismutase (SOD) and malondialdehyde (MDA). Results At the same sampling time, the thymus glands and spleen index and the content of SOD in each dose group were significantly less than control group, The content of MDA was significantly higher than control group. The trends of change in thymus glands and spleen index of the mouse in each group increased and decreased first at the same irradiation dosages and different sampling time. The content of MDA in thymus glands increased with the prolongation of sampling time, and the content of MDA in spleen was a trend of reducing the rise first. The content of SOD in thymus increased first and then decreased with the prolongation of sampling time. The content of SOD in the spleen of irradiated 2.0 Gy, 3.0Gy and 4.0 Gy mouse increased with the sampling time. And in the irradiation of 5.0 Gy, 6.0 Gy group, the content of SOD in the spleen of mouse increased first and then decreased with the prolongation of sampling time. Conclusion The effect of X-rays on immune organs in mouse was positively correlated with the dose of irradiation during the observed dose and measurement time. Different tissue weight recovery times are different, and low-dose irradiation begins to recover time. Higher dose irradiation begins to recover earlier.

Key words: X-ray, Immune organs, Injury