低剂量~（12）C~（6＋）离子辐射诱导的小鼠骨髓细胞适应性反应实验研究

目的研究低剂量重离子辐射（LDR）对小鼠造血系统的适应性反应特征。方法对小鼠给予大剂量（2.0 Gy）12C＋6射线照射前预先采用0.050,0.075 Gy 12C＋6离子束全身照射,其中一批小鼠24 h处死,测定外周血指标、脏器系数、骨髓细胞微核率、骨髓DNA含量;第二批小鼠接受大剂量（2.0 Gy）全身辐照后观察其30 d存活情况。结果与大剂量直接照射组相比,0.050Gy低剂量照射组小鼠外周血白细胞明显升高,骨髓DNA含量升高,小鼠骨髓细胞的微核率降低（均P〈0.05~0.01）,其余指标无统计学差异。0.075 Gy低剂量照射后小鼠外周血白细胞与照射对照组比较有一定下降,其余指标无明显差异。结论低剂量碳离子束照射能拮抗大剂量照射后引起的骨髓细胞损伤,对造血组织产生适应性反应,对重离子治疗肿瘤及放射防护具有一定参考意义。

Experimental Study on Adaptive Response of Bone Marrow Cells Induced by Low-dose 12C+6 Ion Beam Radiation in Mice

Objective To study the characteristics of hematopoietic system adaptive response of low-dose heavy ion 12C＋6 radiation in mice.Methods The mice were irradiated high-dose（2.0 Gy） 12C＋6 in advance of a low-dose（0.050,0.075 Gy） 12C＋6 ion beam total body irradiation,in which a group of mice were killed 24 h and indicators of peripheral blood were measured,organ coefficient,bone marrow cells micronucleus,bone marrow DNA content;mice received one-time 2.0 Gy whole body irradiation,the 30 d survivals were observed.Results Compared with high-dose radiation directly,0.050 Gy low-dose irradiated mice were significantly higher peripheral WBC,bone marrow DNA content increased,mice bone marrow cells micronucleus rate decreased（P 0.05 ~ 0.01）,the other indexes showed no significant difference.0.075 Gy low-dose irradiated mice peripheral blood leukocytes were lower compared with control group,the other index showed no significant difference.Conclusion The low-dose total body irradiation of carbon ion beam irradiation dose antagonized attack reduces the WBC number,bone marrow cells after irradiation reduces the micronucleus rate and bone marrow DNA content significantly increases the average survival time of irradiated mice.The adaptive response of mice bone marrow hematopoietic cells induces excitatory effect in the hematopoietic tissue which has important reference value for cancer radiological therapy and radiological protection of heavy ion beams.