硒对汞致小鼠淋巴细胞DNA损伤的影响

目的　探讨硒对汞致小鼠淋巴细胞DNA损伤的拮抗作用。方法　小鼠同时或先后经腹腔注射 0 .9、0 .3 和0 .1 mg/kg亚硒酸钠与1 .0mg/kg氯化汞水溶液,1次/ d,连续处理2 d;采用单细胞凝胶电泳实验研究上述处理对小鼠淋巴细胞DNA损伤的影响。结果　不同剂量的硒和汞同时染毒时,高硒组其DNA平均迁移长度极显著低于单独汞组(P<0 .01);染汞之前给硒,与单独汞组比较,加硒组其DNA平均迁移长度极显著降低(P<0. 01),且中、低剂量组降低更为明显;染汞之后给硒,3个加硒组其 DNA平均迁移长度极显著低于单独汞组(P<0 .01),硒剂量越高,降低越明显。结论　硒对汞致淋巴细胞DNA损伤有拮抗作用,但这一作用和其染毒剂量及染毒顺序有关。

Effect of selenium on mercury-induced DNA damage in mice lymphocytes

Objective To study the antagonistic effect of selenium(Se) against mercury-induced DNA damage in mice lymphocytes. Methods Mice were injected intraperitoneally with water solution of sodium selenite at 0.9,0.3 and 0.1 mg/kg and mercuric chloride at 1.0mg/kg simultaneously or sequentially, once a day for 2 days. DNA damages in blood lymphocytes were observed by single cell gel electrophoresis(SCGE) . Results When mice were treated simultaneously with different doses of Se and mercury , the average length of DNA migration in high dose Se group decreased obviously, which showed significant difference compared with mercury group(P<0.01). When Se was injected to mice prior to mercury, the average length of DNA migration in Se groups was significantly lower than that of mercury group(P<0.01), and the average length of DNA migration in median and low dose groups was decreased furthermore, when Se was injected to mice behind mercury,the average length of DNA migration of Se groups was decreased respectively which was significantly different to mercury group(P<0.01), and a decrease was much obvious with doses of Se increasing. Conclusion The results suggested that Se can antagonize the toxicity of mercury and this is related to the with exposed dose and the exposed order.