对二氯苯染毒雄性小鼠体细胞与生殖细胞染色体畸变分析

Chromosome Aberration Assay in Somatic and Germ Cells of Male Mice Treated with Para-dichlorobenzene

[目的 ]研究对二氯苯的遗传毒性作用。 [方法 ] 40只雄性昆明种小鼠随机分成 5组 ,每组 8只。实验组小鼠连续 5d分别以 180 0、90 0、45 0mg/kg剂量对二氯苯经口灌胃 ,阴性对照组小鼠以等量花生油灌胃 ,阳性对照组小鼠以40mg/kg剂量环磷酰胺腹腔注射。末次染毒 2 4h后处死动物 ,分析骨髓细胞以及精原细胞与初级精母细胞染色体畸变率。 [结果 ]对二氯苯各剂量染毒组雄性小鼠骨髓细胞以及精原细胞和初级精母细胞染色体畸变率与阴性对照组比较均无统计学显著性增高 (P >0 0 5 ) ,各剂量染毒组初级精母细胞常染色体早熟分离发生率与阴性对照组比较也均无统计学显著性差异 (P >0 0 5 ) ,但高剂量染毒组初级精母细胞性染色体早熟分离发生率非常显著高于阴性对照组 (P <0 0 1)。[结论 ]在本实验剂量下未观察到对二氯苯对骨髓细胞染色体结构畸变的诱发作用 。

To study genotoxic effects of para dichlorobenzene. Forty male Kunming mice were divided randomly into five groups with eight of each group. The mice in the experimental groups were treated with para dichlorobenzene for five consecutive days by oral gavage at a dose of 1 800 , 900 or 450 mg/kg body weight,respectively. The mice in the negative control group were given peanut oil by oral gavage at the same volume. The mice in the positive control group were administered with cyclophosphamide by intraperitoneal injection at a dose of 40 mg/kg body weight. All animals were sacrificed by cervical dislocation 24 hours after the last dosage. Chromosome aberration assays in the bone marrow cells and testicle cells were carried out. Chromosome aberration frequencies in bone marrow cells,spermatogonia and primary spermatocytes in the para dichlorobenzene treated groups were not significantly higher than those in the negative control group ( P >0 05). Precocious separation rate of chromatids in primary spermatocyte autosomes was not elevated significantly in the para dichlorobenzene treated groups than that in the negative control group ( P >0 05),but in sex chromosomes at the dose of 1 800 mg/kg it was elevated significantly than that in the negative control group ( P <0 01). [Conclusion] Para dichlorobenzene has no induction of structral chromosome aberration in bone marrow cells under the experimental conditions,but it has potential adverse effect on precocious separation of sex chromosomes in primary spermatocytes at excessive administration.