除草剂阿特拉津的免疫毒性及其对大鼠免疫功能的影响

目的：检测除草剂阿特拉津（ATR）对大鼠免疫功能的影响，阐明ATR的免疫毒性。方法：32只Wistar大鼠随机分为对照组和低、中、高剂量ATR组（n=8），分别给予0、5、25和125 mg·kg^-1ATR连续灌胃28 d。检测各组大鼠体质量和脾指数；HE染色观察各组大鼠脾脏组织的病理形态表现；采用淋巴细胞转化实验测定各组大鼠脾淋巴细胞转化率；检测各组大鼠NK细胞杀伤活性，流式细胞术检测各组大鼠脾细胞中CD3⁺和CD8⁺T细胞百分比，ELISA实验检测各组大鼠血清中白细胞介素1（IL-1）和白细胞介素6（IL-6）水平。结果：与对照组比较，各剂量ATR组大鼠体质量差异无统计学意义（P>0.05）；与对照组比较，低和中剂量ATR组大鼠脾指数差异无统计学意义（P>0.05），高剂量ATR组大鼠脾指数降低（P<0.05）。HE染色检测，与对照组比较，低剂量ATR组大鼠脾组织无明显变化；中剂量ATR组大鼠脾组织生发中心略减少，高剂量ATR组大鼠脾组织呈现明显退行性变，生发中心消失，白髓减少，红髓充血。NK细胞杀伤活性检测，与对照组比较，各剂量ATR组大鼠NK细胞杀伤活性差异无统计学意义。脾淋巴细胞转化实验，与对照组比较，低和中剂量ATR组大鼠淋巴细胞转化率差异无统计学意义（P>0.05），高剂量ATR组大鼠脾淋巴细胞转化率降低（P<0.05）。流式细胞术检测，与对照组比较，低和中剂量ATR组大鼠脾细胞中CD3⁺和CD8⁺细胞百分比差异无统计学意义（P>0.05），高剂量ATR组大鼠脾细胞中CD3⁺、CD8⁺ T细胞百分比降低（P<0.05）。细胞因子检测，与对照组比较，低和中剂量ATR组大鼠血清中IL-1和IL-6水平差异无统计学意义（P>0.05），高剂量ATR组大鼠血清中IL-1和IL-6水平升高（P<0.05）。结论：高剂量ATR可产生明显的免疫毒性效应。

Immunotoxicity of herbicide atrazine and its effect on immune function of rats

Objective: To detecet the effect of herbicide atrazine(ATR) on immunologic function of the rats, and to clarify the immunotoxicity of ATR.Methods: A total of 32 Wistar rats were randomly divided into control group, low, middle and high doses of ATR groups (n=8); the rats in various groups were given 0,5, 25, and 125 mg·kg^-1 ATR for 28 d, respectively. The body weights and spleen indexes of the rats in various groups were detected; HE staining was used to observe the morphology of spleen tissue of the rats in various groups;lymphocyte transformation assay was used to determine the lymphocyte transformation rates in spleen cells of the rats in various groups; the killing activities of NK cells in spleen cells of the rats in various groups were detected;flow cytometry was used to detect the percentages of CD3⁺ and CD8⁺ T cells in spleen cells of the rats in various groups; ELISA assay was used to detect the serum levels of interleukin-1 (IL-1) and interleukin-6(IL-6) of the rats in various groups.Results: Compared with control group, the body weights of the rats in different doses of ATR groups had no statistically significant differences(P>0.05).Compared with control group, the spleen indexes of the rats in low and middle doses of ATR groups had no statistically significant differences(P>0.05),and the spleen index of the rats in high dose of ATR group was decreased(P<0.05).The HE staining results showed that compared with control group, the morphology of spleen tissue of the rats in low dose of ATR group had no significant changes; the germinal centers of spleen tissue of the rats in middle dose of ATR group were slightly decreased; the morphology of spleen tissue of the rats in high dose of ATR group had obviously degenerative changes, which were characterized by disappearance of germinal centers, diminution of white pulp, and congestion of red pulp. The results of killing activity detection of NK cells showed that compared with control group, the killing activities of NK cells of the rats in different doses of ATR groups had no significant differences(P>0.05).The spleen lymphocyte transformation assay results showed that compared with control group, the lymphocyte transformation rates of spleen cells of the rats in low and middle doses of ATR groups had no significant differences(P>0.05);the lymphocyte transformation rate of spleen cells of the rats in high dose of ATR group was decreased(P<0.05).The flow cytometry results showed that compared with control group, the percentages of CD3⁺ and CD8⁺ T cells of the rats in low and middle doses of ATR groups had no significant differences(P>0.05),and the percentages of CD3⁺ and CD8⁺ T cells of the rats in high dose of ATR group were decreased(P<0.05).The cytokine detection results showed that compared with control group, the serum levels of IL-1 and IL-6 of the rats in low and middle doses of ATR groups had no signifiant differences(P>0.05),and the serum levels of IL-1 and IL-6 of the rats in high dose of ATR group were increased(P<0.05).Conclusion: High dose of ART can induce the obvious immunotoxicity.