地鼠和人胚肺上皮细胞对致癌剂毒性和染色体损伤反应

为了检查人染色体比啮齿类动物染色体更为稳定的假设,我们比较了人和叙利亚地鼠胚胎肺上皮细胞对诱导性细胞毒性,染色体畸变和姐妹染色体交换(SCE)的敏感性。接种细胞一天后,用不同剂量乙基亚硝基脲(ENU)处理2小时,然后用标准法检查其染色体畸变和SCE率,用细胞计数法测定细胞毒性。染色体畸变和SCE率均表明清楚的剂量依赖关系,而且在地鼠细胞的发生率明显高于人细胞,但两种细胞表明相同的细胞毒性反应。这些结果提示人细胞染色体比地鼠细胞染色体更为稳定和细胞毒性反应不一定总是与染色体损伤有关。

Toxicity and Chromosomal Damage Induced by Carcinogen in Fetal Syrian Hamster and Human Pulmonary Epithelial Cells

In order to test the hypothesis that human chromosomes are more stable than those of rodents, we compared the fetal human and Syrian hamster pulmonary epithelial cell lines for their sensitivity to the induction of cytotoxicity (CT), chromosomal aberrations(CAs) and sister chromatid exchanges (SCEs). One day after plating, the cells were exposed for 2 h to various doses of ethylnitrosourea (ENU). CAs and SCEs were examined by the standard methods, while CT was determined by cell counts. The frequency of CAs and that of SCEs showed clear dose dependency and was remarkably higher in the hamster than in the human cells. CT showed a similar dose response for both cell lines. These results suggest that human chromosomes are indeed more resistant to ENU-inducible aberratins than hamster chromosomes and that CT may not always be directly associated with chromosomal damage.