松果菊苷对脑缺血大鼠纹状体细胞外液中羟自由基含量的影响

 目的 研究松果菊苷(ECH)对局灶型脑缺血大鼠纹状体细胞外液中羟自由基的影响，以探讨ECH对脑缺血保护作用的可能机制。方法 SD大鼠随机分为对照组、模型组、ECH高、低剂量组和川芎嗪(CXQ)组。各组大鼠给予相应的药物或生理盐水腹腔注射，每天1次，连续7 d。给药第3天，脑纹状体埋置探针套管。末次给药1 h后，制作大鼠局灶性脑缺血模型(MCAO)，造模后立刻以水杨酸格林透析液进行微透析，将透析液注入高效液相色谱-电化学检测器(HPLC-ECD)测定各组纹状体细胞外液中2，3-二羟基苯甲酸（2，3-DHBA），2，5-二羟基苯甲酸（2，5-DHBA）的含量。结果 与对照组相比，模型组2，3-DHBA、 2，5-DHBA水平升高，与模型组比较，ECH高、低剂量组(30，15 mg·kg^-1·d^-1)和CXQ组(30 mg·kg^-1·d^-1) 2，3-DHBA，2，5-DHBA含量均有所降低。结论 ECH对脑缺血的保护作用可能与对抗脑缺血后羟自由基的升高有关。

Effects of Echinacoside on Striatal Extracellular Levels of Hydroxyl Radical in Cerebral Ischemia Rats

OBJECTIVE To examine the effects of echinacoside(ECH) on striatal extracellular levels of hydroxyl radical in cerebral ischemia rats and its possible mechanism of anti-cerebral ischemia.METHODS Rats were divided into control,model,ECH high and low dose and CXQ groups randomly.Every rat was administered drugs or vehicle through intraperitoneal injection,one time a day for 7 consecutive days.At day 3,focal ischemia was generated by permanent middle cerebral artery occlusion(MCAO).Then the striatal extracellular fluids were gained by brain microdialysis.High performance liquid chromatography with electrochemical detection was used to measure the striatal extracellular levels of hydroxyl radicals.RESULTS The levels of 2,3-DHBA,2,5-DHBA increased rapidly.Compared with the model group,administration of ECH of high and low dose(30,15 mg·kg-1·d-1) and CXQ(30 mg·kg-1·d-1) successfully prevented the elevation of 2,3-DHBA and 2,5-DHBA.CONCLUSION ECH can reduce striatal extracellular levels of hydroxyl radical,which may be one of its mechanisms of anti-cerebral ischemia.