摘要:
为了评估低剂量X射线连续辐射对BALB/c小鼠健康机体免疫系统的影响,实验采用X射线全身连续照射BALB/c小鼠,照射第一天剂量为0.07 Gy,剂量率0.2 Gy/min,之后每天照射0.08 Gy,共照射12 d,累积剂量1.03 Gy,照射后24和48 h取血、胸腺和脾脏.流式细胞仪检测免疫细胞周期和凋亡的变化,胸腺和脾脏指数用重量法获取.实验结果表明,小鼠胸腺细胞的周期在照射后24 h被阻滞在G_2/M期;外周血淋巴和胸腺细胞周期48 h被阻滞在G_0/G_1期,细胞凋亡比例在照射后两个时间点都显著增加;脾脏淋巴细胞周期24 h被阻滞在G_0/G_1期,48 h被阻滞在S期,细胞凋亡比例在24和48 h显著减少;脾脏指数在照射后48 h显著减少.故低剂量X射线连续全身照射BALB/c小鼠可激活免疫细胞不同的周期监测点,引起免疫细胞凋亡比例发生变化,造成一定的辐射损伤,且这种影响随着免疫器官的不同而不同.
Abstract:
For estimating the effect of low doses X-ray continual irradiation to immunity system of mouse,BALB/c mice were continually irradiated to 1.03 Gy by X rays at a dose rate of 0.2 Gy/min in 13 d.At 24or 48 h after irradiation,the immunocyte cycle and apoptosis were determined by flow cytometry,and the thymus and spleen weights were measured too.The results showed that the cycle of thymocyte were arres-ted in G_2/M at 24 h,the number of peripheral blood lymphocytes and thymocytes in G_0/G_1 phase at 48 h was up and the percentage of apoptosis had a significance increase in both of time points;the cycle of spleen lymphocytes was delayed in G_0/G_1 at 24 h,in S phase at 48 h,the apoptosis had a significance de-crase at 24 and 48 h;spleen index declined significantly at 48 h.The results suggested that low doses con-tinual X-ray whole-body irradiation could activate different cell cycle checkpoints,and resuIt in some chan-ges of apoptosis and some damages to immunocytes.The continual X-ray irradiation affects the organs dif-ferently,it might provide experiment basis for radioprotection.