阿特拉津对BALB／c小鼠T淋巴细胞功能的影响

Effects of atrazine on T lymphocytes function in BALB /c mice

目的探讨阿特拉津对小鼠T淋巴细胞功能的影响。方法健康BALB/c小鼠按体重随机分为阿特拉津高剂量组(400 mg/kg)、中剂量组(200 mg/kg)、低剂量组(100 mg/kg)和阴性对照组(蒸馏水),经口灌胃,每天1次,连续21 d。试验结束后,眼球取血,处死小鼠,观察胸腺组织病理学变化,采用MTT还原法和流式细胞仪分别检测脾脏T淋巴细胞增殖情况和胸腺T淋巴细胞亚群分布,酶联免疫吸附法检测血清中白细胞介素-2(interleukin-2,IL-2)和白细胞介素-4(interleukin-4,IL-4)含量。结果阿特拉津暴露使小鼠胸腺皮质细胞减少,各剂量组脾脏T淋巴细胞转化率低于阴性对照组(均有P<0.05)。阿特拉津中、高剂量组胸腺CD3+T淋巴细胞亚群比例以及CD4+T/CD8+T比值均低于阴性对照组(均有P<0.05),各剂量组CD4+T淋巴细胞亚群比例均明显低于阴性对照组(均有P<0.05),CD8+T淋巴亚群比例随染毒剂量增高有降低趋势,但差异无统计学意义(均有P>0.05)。阿特拉津高剂量组血清IL-2和IL-4含量明显降低(均有P<0.05)。结论阿特拉津能抑制小鼠T淋巴细胞功能,因而有免疫毒性作用。

Objective To explore the effect of atrazine on T lymphocytes function in mice. Methods BALB/c mice were randomly divided into atrazine groups （400 mg/kg, 200 mg/kg and 100mg/kg, respectively） and the negative control group （distilled water）. Mice were administrated to atrazine or distilled water by oral gavage, once a day for 21 days. Then eye blood was collected and the pathological changes of thymus were observed. Splenic T lymphocytes prolifera- tion and subsets distribution of thymic T lymphocytes were determined with MTI＂ reduction method and flow cytometry, re- spectively. IL-2 and IL-4 in serum were measured using enzyme linked immunosorbent assay. Results Atrazine exposure resulted in decrease of thymus cortex cells and T lymphocytes transformation rate decreased significantly （P 〈 0. 05 ）. The proportion of thymic CD3 ~ T lymphocytes subset, and CD4＋/CD8＋ ratio in 400mg/kg and 200mg/kg atrazine groups were lower than those in the control group （P 〈 0. 05）. CD4＋ T lymphocytes subset in different atrazine groups were lower than those in the control group （ P 〈 0. 05）. Although the proportion of CD8＋T lymphocytes subset showed decreasing trend with increasing dose, there was no statistical significance. Serum IL-2 and IL-4 level in the 400mg/kg atrazine group were significantly lower than those in the control group （P 〈 0. 05）. Conclusions Atrazine decreases T lymphocytes function and shows the immunotoxicity.