体内外微核试验评价亚硒酸钠的致突变性和抗突变性

Detection of Mutagenicity and Antimutagenicity of Sodium Selenite in Vivo and Vitro Micronucleus Test

目的评价亚硒酸钠(Na2SeO3)的致突变性和抗突变性。方法使用体外和体内微核试验。体外试验设阴性对照组、阳性对照组、抗突变对照组,以及致突变和抗突变试验各5组,处理L5178Y细胞3 h、低渗、固定、制片。体内试验设阴性对照组、阳性对照组,以及致突变和抗突变试验各4组,昆明种小鼠连续灌胃5 d,末次灌胃后24 h处死小鼠,取骨髓制片,染色,观察。结果体外试验中,3～24μg/ml Na2SeO3致突变试验组的细胞微核率与阴性对照组相比差异有统计学意义,0.2～3.2μg/ml Na2SeO3抗突变试验组的细胞微核率均比丝裂霉素C(MMC)对照组低,差异有统计学意义;体内微核试验中,6.32、7.90 mg/kg.bw剂量组的小鼠骨髓细胞微核率与阴性对照组相比差异有统计学意义,0.04～0.32 mg/kg.bw剂量组的微核率明显低于环磷酰胺(CP)对照组,差异有统计学意义。结论亚硒酸钠在一定的剂量范围内表现出致突变作用,而在不同的剂量范围内又可拮抗CP和MMC引起的遗传损伤。

Objective To evaluate the mutagenic and antimutagenic effects of sodium selenite.Methods Negative control groups,positive control groups,mutagenic control groups and anti-mutagenic groups at 5 concentration levels of sodium selenite were set in vitro micronucleus test;L5178Y cells were treated respectively for 3h.Slide specimen were fixed and dried after hypotonic treatment.In vivo test,positive groups and negative groups,mutagenic and anti-mutagenic groups at 4 concentration levels of sodium selenite were set.Mice were administered by gavage once a day for 5 d consecutively,and sacrificed at 24 h after the last administration.Bone marrow was used to make slide speciments,which were dyed with Giemsa and then counted by light microscope.ResultsIn vitro test,the percentage of micronucleated cell（MNC） increased significantly at dose groups from 3 μg/ml to 24 μg/ml and the MNC% of the groups with concentration from 0.2 μg/ml to 3.2 μg/ml was lower significantly than MMC control.In vivo test,the MNC% were significantly increased in mutagenic groups at the concentration of 6.32,7.90 mg/kg.bw than the negative control the MNC% of the anti-mutagenicity groups were reduced significantly than cyclophosphamide control.Conclusions Under this experimental condition,sodium selenite showed mutagenic effect at a certain dose range and antimutagenic effect at a different dose range.