低剂量辐射诱导小鼠胸腺细胞周期进程的适应性反应  

Adaptive response of thymocyte cycle progression induced by low dose ionizing radiation in mice

作　　者：龚守良[1] 刘淑春[1] 吕喆[1] 王珍琦[1] 刘扬[1] 刘光伟[1] 刘树铮[1] 

机构地区：[1]吉林大学公共卫生学院卫生部放射生物学重点实验室,长春130021

出　　处：《辐射研究与辐射工艺学报》2004年第3期176-180,共5页Journal of Radiation Research and Radiation Processing

基　　金：国家自然科学基金(39170275)资助

摘　　要：观察低剂量辐射诱导小鼠胸腺细胞周期进程适应性反应的剂量、剂量率和时间效应。用诱导剂量(D1:25、50、100、200mGy,剂量率:12.5mGy/min;;D1:75mGy,剂量率:6.25、12.5、25、50、100、200mGy/min)和攻击剂量(D2:1.0、1.5、2.0Gy,剂量率:287mGy/min)照射Kunming雄性小鼠,D1和D2间隔3、6、12、24、60h。用流式细胞仪检测胸腺细胞周期各时相细胞百分数。当D1为25、50、100mGy(剂量率:12.5mGy/min,D1和D2间隔6h),或D1为75mGy(剂量率:6.25、12.5、25mGy/min,D1和D2间隔3、6、12h),D2为1.0、1.5、2.0Gy,D2组与假照射组之比S期胸腺细胞百分数明显降低(p<0.05或p<0.01),而G0/G1和G2+M期细胞百分数明显增加(p<0.05或p<0.01);;但D1+D2组与D2组之比S期细胞百分数明显增加(p<0.05或p<0.01),而G0/G1和G2+M期细胞百分数不同程度降低。小鼠接受1.0—2.0Gy(287mGy/min)照射前3—12h受25—100mGy(6.25—25mGy/min)照射,可诱导胸腺细胞周期进程的适应性反应。In this paper, dose-, dose rate- and time?effect of adaptive response of thymocyte cycle progression induced by low dose radiation were observed. Kunming mice were irradiated with different inductive doses ( D1) of 25, 50, 100 and 200mGy at a fixed dose rate of 12.5mGy/min, or a fixed inductive dose (D1) of 75mGy with different dose rates of 6.25, 12.5, 25, 50, 100 and 200mGy/min. The mice were then irradiated with different challenging doses ( D2) of 1.0, 1.5 and 2.0Gy at a fixed dose rate of 287mGy/min. The time intervals between D1 and D2 were 3, 6, 12, 24 and 60h. Thymocyte cycle progression was measured with flow cytometer. It has been found that with the mice which had received D1 of 25, 50 and 100mGy at 12.5 mGy/min dose rate and the D2 doses 6h after the D1, or D1 of 75mGy at dose rates of 6.25, 12.5 and 25mGy/min and the D2 doses 3, 6 and 12h after the D1, or D2 of 1.0, 1.5 and 2.0Gy, the percentage ratio of S phase thymocytes decreased significantly (p<0.05 or p<0.01), and the percentage of G0/G1 and G2+M phase thymocytes increased significantly (p<0.05 or p<0.01).too, by comparing the D2 groups to the sham?irradiation group, Comparing the D1+D2 groups to the D2 groups, however, the percentage ratio of S phase thymocytes increased significantly (p<0.05 or p<0.01), and the percentage of G0/G1 and G2+M phase thymocytes decreased in varying degrees. The results suggest that irradiating the mice to 25—100mGy at dose rates of 6.25— 25mGy/min 3—12h before exposing them to 1.0—2.0Gy irradiation at 287mGy/min dose rate, the adaptive response of thymocyte cycle progression could be induced under the condition of whole?body irradiation.

关 键 词：低剂量电离辐射 细胞周期进程 适应性反应 

分 类 号：R811.5[医药卫生—放射医学] Q235[医药卫生—临床医学]