Griffin C S, Harvey A N, Savage J R
MRC Radiobiology Unit, Chilton, Didcot, UK.
Int J Radiat Biol. 1994 Jul;66(1):85-98. doi: 10.1080/09553009414550971.
The comparative induction of chromatid aberrations by 238Pu alpha-particles, or by 250 kVp X-rays was investigated in V79 Chinese hamster cells. Metaphases were sampled at hourly intervals postirradiation up to 8 h and BrdU/FPG staining methods were used to distinguish G2, S and G1 phase cells. Two experiments were performed. In the first, an alpha-particle dose of 0.41 Gy was compared with an X-ray dose of 1.5 Gy used in a previously published study. In the second, an X-ray dose of 1.2 Gy was used in parallel with 0.41 Gy of alpha-particles to produce a similar overall frequency of interchanges, and allow comparative ratios to be derived for other aberration types. At these isoexchange doses, alpha-particles produce relatively less gaps and breaks, particularly in late G2, and significantly more isochromatid deletions. A very high proportion of the isochromatid deletions were incomplete after alpha-particles compared with X-rays, but no difference in incompleteness was found for interchanges. With X-rays, about 6% of interchanges are complex intra-interchange forms. At similar exchange frequencies this increases to 26.7% for alpha-irradiation, suggesting increased multiple lesion interaction. Differences in dose distribution between alpha-particles and X-rays are discussed and mitotic delay is examined after separation of the analysed cells into damaged and undamaged classes.
在V79中国仓鼠细胞中，研究了238Puα粒子或250 kVp X射线对染色单体畸变的诱导作用。在照射后长达8小时内，每隔一小时采集一次中期相，并使用BrdU/FPG染色方法区分G2、S和G1期细胞。进行了两个实验。在第一个实验中，将0.41 Gy的α粒子剂量与先前发表的研究中使用的1.5 Gy X射线剂量进行比较。在第二个实验中，将1.2 Gy的X射线剂量与0.41 Gy的α粒子剂量平行使用，以产生相似的交换总频率，并得出其他畸变类型的比较比率。在这些等交换剂量下，α粒子产生的间隙和断裂相对较少，尤其是在G2晚期，而等染色单体缺失则明显更多。与X射线相比，α粒子照射后，等染色单体缺失的很大一部分是不完全的，但在交换方面未发现不完全性的差异。对于X射线，约6%的交换是复杂的交换内形式。在相似的交换频率下，α粒子照射时这一比例增加到26.7%，表明多重损伤相互作用增加。讨论了α粒子和X射线之间剂量分布的差异，并在将分析细胞分为受损和未受损类别后检查了有丝分裂延迟。
