口服二苯胂酸在小鼠小脑蒲肯野细胞诱发氧化和氮化应激

为了研究口服化学战剂降解产物二苯胂酸(DPA)导致小脑功能异常与诱发小鼠小脑蒲肯野细胞氧化和氮化应激之间的关系,利用硫代巴比妥酸反应物(TBARS)法和免疫组织化学方法检测脑组织丙二醛(MDA)和3-硝基酪氨酸(3-NT)的变化情况.同时,通过在体外合成3价DPA的模型化合物二苯胂酸碘(DPI),并用Western-blot检测3-NT的生成.研究发现,在小鼠一次口服15mg·kg-1DPA以及连续5d口服5mg·kg-1 DPA的情况下,小脑组织TBARS上升,蒲肯野细胞MDA和3-NT染色阳性.体外实验检测到DPI和NO反应可以生成3-NT,这表明DPA会导致小鼠小脑功能异常,这与其在体内代谢过程中产生的砷相关活性物质在小脑蒲肯野细胞诱发氧化和氮化应激密切有关.

Oral administration of diphenylarsinic acid induces oxidative and nitrosative stress in cerebellar Purkinje cells of mice

The prominent cerebellar symptoms due to exposure to diphenylarsinic acid (DPA), a stable degradation product of chemical warfare agents, were elucidated by investigating the DPA-induced oxidative and/or nitrosative stress in cerebellar Purkinje cells of mice. The values of thiobarbituric acid-reactive substances (TBA-RS) were measured in the brain of mice after oral administration of DPA. Malondialdehyde (MDA)-adducts and 3-NT were detected in cerebellar sections by immunohistochemical analysis. Significantly positive staining with malondialdehyde (MDA) and 3-nitrotyrosine (3-NT) was observed in the cerebellar Purkinje cells by repeated administration (5 mg·kg-1·d-1) with DPA for 5 weeks. A single administration of DPA (15 mg·kg-1) led to cerebellar symptoms from a behavioral pharmacology standpoint. The present results suggest the possibility that novel arsenic-associated active species may be a factor underlying the oxidative and nitrosative stress in Purkinje cells due to exposure to DPA, and that the damage may lead to the cerebellar symptoms.