轻稀土对乐果致蚕豆根尖细胞遗传毒性的影响  

Effects of light rare-earth elements on the cytogenotoxicity induced by dimethoate to root tips of Vicia faba

作　　者：汪承润[1] 施翠娥[1] 谢影[1] 

机构地区：[1]淮南师范学院化学生物系,安徽淮南232001

出　　处：《安全与环境学报》2007年第2期4-9,共6页Journal of Safety and Environment

基　　金：安徽省教育厅自然科学基金项目(2005KJ197);淮南市自然基金项目(2004119)

摘　　要：研究了农药乐果与轻稀土乐果混合溶液对蚕豆根尖的细胞遗传毒性,探讨了稀土修复和稀土预处理对乐果染毒根尖的细胞遗传毒性的影响。结果表明,农药乐果具有轻度的遗传毒性和明显的细胞毒性。在相同剂量乐果溶液(体积比1/2000或1/4000)和相同修复时间(24h或48h)下,随着稀土剂量的增加,根尖分裂指数逐步下降,而微核率和细胞核异常率呈上升趋势。30μmol·L-1稀土分别与1/2000和1/4000乐果溶液混合染毒根尖5h,30μmol·L-1稀土溶液修复24h,前者分裂指数和微核率低于后者,但二者分裂指数均低于该剂量稀土或乐果的单独作用结果。低剂量稀土(1.2μmol·L-1、6μmol·L-1)与乐果混合染毒在一定程度上刺激了根尖细胞的分裂,降低了微核率和核异常率,且延长修复时间可进一步提高分裂指数,降低微核率和核异常率。另外,低剂量稀土溶液(1.2μmol·L-1、6μmol·L-1)预处理根尖后再进行乐果染毒,与乐果染毒组比较提高了细胞分裂指数并降低了微核率。据此推测,高剂量稀土溶液(>30μmol·L-1)可能增加了乐果溶液对蚕豆根尖的细胞遗传毒性,而低剂量稀土溶液(<6μmol·L-1)可能具有促进乐果染毒后的根尖细胞修复损伤的作用。The present paper aims to report its investigation of the cy togenotoxicity induced by dimethoate separately or jointly with the light rare earths to the root tips of Vicia labs. At the same time, it has further investigated the recovery or pretreatment effects with rareearth solutions on the root tips. The results of our investigation show that dimethoates with slight genotoxicity or serious cytotoxicity may all affect the root tips; and that beth the micronucleus frequency and the nucleus abnormity, when treated with the same dimethoate solutions or subjected to the same recovered period will help to noticeably increase by adding the dose of rare earths. Meanwhile, the mitotic index would dechne gradually. Incubated in the combination of 30 μmol·L^-1 light rare-earth with 1/2000 or 1/4000 （ V/ V） dimethoate for 5 h and then let-it-be-recovered for 24 h in 30 μmol·L^-1 light rare-earth solution respectively, the mitotic index and the micronucle- us frequency of the root tips in the former would be less than those in the latter, respectively. Nevertheless, the mitotic index beth in the former and in the latter would be less than those induced by 30 μmol·L^-1 light rare-earth solution or the corresponding dimethoate solution singly. The low dose of light rare-earth （1.2 μmol·L^-1 and 6 μmol·L^-1 ）, combined with dimethoate solutions, prove to be able to stimulate the mitosis and decrease the frequencies of micronuclei and nucleus abnormity, which would be accelerated as a result of prolonging the recovery process. Furthermore, as compared to the dimethoate-treated groups, the mitotic indexes would increase and the micronucleus frequencies would decline in the root tips, when pretreated with low dose light rare-earth solution （ 1.2 μmol·L^-1 and 6 μmol·L^-1） before dimethoate poisoning. Therefore, it is suggested that cytogenotoxicity induced by dimethoate would noticeably be enhanced by high doses of light rare-earth solution （ 〉 30 μmol·L^-1）, and that the recovery from dim

关 键 词：遗传毒理学 轻稀土 乐果 微核率 分裂指数 核异常 细胞遗传毒性 

分 类 号：O614.33[理学—无机化学]