Study of the Immunotoxicity of Atrazine after Subacute Exposure to Mice

摘要

Hie hnmunotoxic effect of atrazine (ATZ) ,a kind of herbicide that has been used widely in agriculture and detected frequently in water and other environments, was investigated using male Balb/c mice with a panel of immune function assays. Male Balb/c mice of SPF grade were randomly divided into five groups. Atrazine was administered by gavage at doses of 175,87.5,and 43.73 mg/kg ? bw ? day,and cyclophosphamide (CP) at dose of 40mg/kg ? bw ? day as positive control,and corn oil was administered as negative control for 28 consecutive days. After 28days exposure, Body weight, organ weight, antibody aggregation of serum hemolysin, T lymphocyte proliferation, delayed type hypersensitivity, NK cells activity, clearance of neutral red of abdominal macrophages, spleen and thy-mus cells apoptosis and necrosis,LL-4,IFN-γproduction of splenocytes,IL-1 and TNF-a production and NO releasing of abdominal macrophages,and serum lysozyme were determined. It showed that compared with negative control group,cell-mediated,humoral activity of the immune system as well as non-specific immune function in highdose group of ATZ was suppressed,and NO release and IFN-γ/IL4 was significantly decreased. No significant change was observed in ATZ medium-dose group in serum hemolysin,DTH.NK activity and NO release,but significantly lowered proliferation response to ConnavalinA (ConA) and production of IFN-γwas observed compared with negative control group. No significant change in humoral immune activity and cytokine and no production was observed in low-dose group of ATZ, but proliferation response to ConA was significantly decreased compared with negative control group. Serum lysozyme was decreased in a dose-response way in all ATZ treated group,early apoptosis of thyrnus cells was increased significantly in ATZ at high and medium-dose of ATZ. ATZ showed different extent of inhibitory effect on cell-mediated immunity, humoral immunity, as well as non-specific immune function of mice,and cell-mediated immune function is more susceptible to ATZ. The presence of this herbicide in environments might alter immune response of humans,and its mechanisms need further studies.