中文摘要：

目的观察大鼠大脑皮层梗死后丘脑腹后外侧核（ventroposterior nucleus of the thalamus，VPN）的继发性损害是否有DNA氧化损伤，并研究抗氧化剂依布硒啉（ebselen，EB）对这种远隔部位损伤是否具有改善作用。方法采用易卒中型肾血管性高血压大鼠（stroke-prone renovascular hypertensive rats，RHRSP），建立大脑中动脉皮层支闭塞（middle cerebral artery occlusion，MCAO）模型后分为：①假手术组，②模型组，③溶剂组，④抗氧化剂EB10mg·kg^-1组，⑤抗氧化剂EB30mg·kg^-1组，每组5只大鼠。2周后行肢体运动神经功能评估并取VPN后行尼氏染色，免疫组化检测VPN的8-羟基-2-脱氧鸟苷（8-hydroxy-2-deoxyguanosine，8-ohdG）表达。结果EB10mg·kg^-1组和EB30mg·kg^-1组神经功能评分优于假手术组（1．80±0．56，1．72±0．48vs2．28±0．33，P〈0．05）。尼氏染色可见假手术组同侧VPN细胞形态规整。而梗死同侧VPN神经细胞出现细胞体积变小，胞核固缩，尼氏体退变为萎缩的深色细胞。EB30mg·kg^-1组尼氏染色观察到改善作用。溶剂组同侧VPN的8-ohdG阳性细胞数目（0．1mm^2）显著增加（146．8±12．1vs108．4±19．2，P〈0．05）；与溶剂组相比，EB10mg·kg^-1组和EB30mg·kg^-1组阳性细胞数目显著下降（123．6±14．7，123．4±17．4vs146．8±12．1，P〈0．05）。结论实验性大脑皮层梗死后2周，同侧VPN存在DNA氧化性损伤。抗氧化剂EB对VPN的DNA氧化损伤有抑制作用，并可改善神经功能。

英文摘要：

Objective To investigate the oxidative DNA damage within the ventroposterior nucleus of the thalamus （VPN） after focal cortical infarction, and explore the effects of ebselen on the oxidative DNA damage after cerebral cortex infarction in hypertensive rats. Methods Middle cerebral artery occlusion （MCAO） was induced in stroke-prone renovascular hypertensive rats, and the rats were randomly divided into five groups ： sham operation group, ischemia group, vehicle group and ebselen （ 10 or 30 mg·kg^-1 ） group. Each group had five animals. Two weeks after the MCAO, the VPN from each group was sectioned and stained with Nissle after neurological function evaluation. Oxidative damage was determined by 8-hydroxy-2-deoxygnanosine （8-ohdG） immunohistochemistry. Results Neurological scores of ebselen （ 10 or 30 mg·kg^-1 ） groups significantly lower than these of vehicle group （ 1.80 ± 0. 56, 1.72 ± 0. 48 vs 2. 28 ± 0. 33, P 〈 0. 05, respectively）. Nissle staining showed that all cells in the ipsilateral VPN of the vehicle group exhibited normal features and MCAO resulted in cells shrinkage of the nucleus and cytoplasm, and atrophic dark cells, the ipsilateral VPN brain Administration of ebselen 30mg·kg^-1 obviously ameliorated the VPN damage on Nissl-stained slices. Compared with vehicle group, increase in number of 8-ohdG positive cells （0. 1 mm^2 ） were detected in ipsilateral VPN （ 146. 8 ± 12. 1 vs 108.4 ± 19. 2, P 〈0.05）. Administration of ebselen at 10 mg·kg^-1 or 30mg·kg^-1 decreased the level of 8-ohdG （ 123.6 ± 14.7 and 123.4 ± 17.4 vs 146. 8 ± 12. 1, P 〈0. 05）. Conclusions After two weeks, there is a marked increase of DNA oxidative stress, ebselen can obviously decrease DNA oxiditive stress in VPN and improve the neurological function.