在Allium cepa细胞中,β-辐射剂量率对诱导的细胞遗传终点的影响
Erison Fonseca Dos Santos1, Magno Nogueira Xavier1, July Anne Torres Novaes1
1Biophysical Dosimetry Laboratory, Department of Physics, Federal University of Sergipe, Av. Marechal Rondon, s/n, Jd. Rosa Elze, 49.100-000, São Cristóvão, Sergipe, Brazil.
概括
贝塔辐射暴露会增加Allium cepa根细胞中的微核 (MN) 频率,但剂量率会显著影响结果. 更高的剂量率可能会显示由于细胞死亡而导致的损伤减少,突出显示需要仔细的剂量测量.
科学领域:
- 辐射生物学 辐射生物学
- 基因毒理学 基因毒理学
- 植物科学 植物科学
背景情况:
- 电离辐射会导致DNA损伤,突变和细胞死亡.
- 在Allium cepa中微核 (MN) 测定是评估辐射诱导的基因组损伤的可靠方法.
研究的目的:
- 为了研究β辐射对Allium cepa根干细胞的影响.
- 在不同的吸收剂量和剂量速率下分析微核 (MN) 形成和线粒体指数 (MI).
主要方法:
- 使用90Sr+90Y源,Allium cepa根暴露于不同剂量速率 (7.2,13.8,19.5mGy/s) 的β辐射 (0.72 Gy,2 Gy,4 Gy) 中.
- 在根固定,染色和显微镜检查后,分析了微核频率和线粒指数.
- 使用ANOVA和图基测试 (p <0.05) 进行了统计分析.
主要成果:
- 在最低和最高的剂量率下,MN频率随着吸收剂量的增加而增加,大多数细胞显示单个MN.
- 细胞保持了线粒活动,即使在最高剂量速率下受到辐射诱导的损伤.
- 在中间剂量速率下,更高的剂量导致了MN频率的降低,这可能是由于细胞死亡的增加.
结论:
- 剂量速率是使用Allium cepa MN试验进行辐射剂量计的关键因素.
- 在某些剂量率下增加细胞死亡可能导致低估辐射诱导的基因组损伤.
- 对于精确的辐射剂量计,对MN频率和线粒体指数的综合分析至关重要.
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