Padovani L, Appolloni M, Anzidei P, Tedeschi B, Caporossi D, Vernole P, Mauro F
Environmental Department, ENEA Casaccia, Rome, Italy.
Mutat Res. 1995 Nov;332(1-2):33-8. doi: 10.1016/0027-5107(95)00120-5.
Several studies suggest that cells appear to become less susceptible to the induction of radiation damage, and in particular of chromosome and chromatid aberrations in short-term cultures of human lymphocytes, when a challenge exposure to ionizing radiation is preceded by a low 'adaptive' dose. Contradictory results have been reported on the conditions under which the phenomenon can be evidenced. In the present work, circulating lymphocytes of 13 children contaminated from the fallout after the Chernobyl accident were tested for their capability to exhibit an adaptive response in experiments in which the challenge dose was administered to stimulated lymphocytes in the S-G2 phase. Furthermore, the possible influence of 3-aminobenzamide, an inhibitor of poly(ADP-ribose) polymerase, was also investigated. Our results indicate that, at least in the instance of the end-point here used (chromosome and chromatid aberrations, the former resulting possibly from the Cs burden), human lymphocytes, chronically exposed to low doses from fallout, do not exhibit any decreased susceptibility to ionizing radiation. However, as reported in the accompanying paper, the same samples appear to show an 'adaptive' response when exposed to a challenge treatment with bleomycin (B. Tedeschi et al., 1995, this issue).
多项研究表明，当在受到电离辐射的激发照射之前给予低“适应性”剂量时，细胞似乎对辐射损伤的诱导变得不那么敏感，尤其是在人淋巴细胞短期培养中对染色体和染色单体畸变的诱导。关于能够证明该现象的条件，已有相互矛盾的结果报道。在本研究中，对13名切尔诺贝利事故后受沉降物污染的儿童的循环淋巴细胞进行了测试，检测它们在将激发剂量给予处于S-G2期的受刺激淋巴细胞的实验中表现出适应性反应的能力。此外，还研究了聚（ADP-核糖）聚合酶抑制剂3-氨基苯甲酰胺的可能影响。我们的结果表明，至少就此处所使用的终点（染色体和染色单体畸变，前者可能由铯负荷导致）而言，长期受到沉降物低剂量照射的人淋巴细胞对电离辐射并未表现出任何敏感性降低。然而，正如随附论文中所报道的，当用博来霉素进行激发处理时，相同的样本似乎表现出“适应性”反应（B. 泰德斯基等人，1995年，本期）。
