松果菊苷对脑缺血大鼠双侧脑组织中单胺类神经递质的影响

Effect of echinacoside on monoamine neurotransmitters in bilateral brain tissue of rats with cerebral ischemia

目的:研究对比大鼠脑缺血后缺血区和非缺血区单胺类神经递质及其代谢产物的变化,考察松果菊苷(ECH)对大鼠脑缺血后双侧脑组织中单胺类神经递质及其代谢产物的影响。方法:SD大鼠随机分为假手术对照组、模型组、ECH高、低剂量组(30,15 mg.kg-1.d-1)和川芎嗪组(CXQ,30 mg.kg-1.d-1)。各组大鼠腹腔注射相应的药物或生理盐水,qd,连续7 d。于给药d 3,进行大脑双侧脑组织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),造模后立刻进行微透析,将透析液注入高效液相-电化学检测器(HPLC-ECD),测定各组缺血后300 min内纹状体细胞外液中去甲肾上腺素(NE)、多巴胺(DA)、3,4二羟苯乙酸(DOPAC)、5-羟色胺(5-HT)和5-羟基吲哚乙酸(5-HIAA)的含量。结果:与假手术组相比,各模型组脑缺血后两侧脑组织细胞外液中5种物质水平均升高;与模型组比较,ECH高、低剂量组与CXQ组5种物质的峰值含量均有所降低。结论:大鼠脑缺血后,非缺血区单胺类神经递质及代谢产物升高,ECH对抗脑缺血损伤的作用可能与降低脑内单胺类神经递质的升高有关。

Objective： To investigate the effect of echinacoside（ECH） on levels of monoamine neurotransmitters in bilateral brain tissue in rats with focal cerebral ischemia,and to investigate the neuroprotective effect of ECH.Methods： Rats were administered with ECH（30,15 mg·kg^-1·d^-1）,CXQ（30 mg·kg^-1·d^-1） or vehicle through intraperitoneal injection,once a day for seven consecutive days.At day 3,focal cerebral ischemia was induced by permanent middle cerebral artery occlusion（MCAO）.Then,extracellular fluids were gained from the striatum by brain microdialysis.High performance liquid chromatography with electrochemical detection was used to measure extracellular levels of NE,DA,DOPAC,5-HT,and 5-HIAA in the striatum.Results： Compared with shame group,the levels of NE,DA,DOPAC,5-HT,and 5-HIAA increased rapidly in bilateral brain tissue after MCAO.Compared with MCAO group,ECH and CXQ successfully prevented elevation of the extracellular levels of NE,DA,DOPAC 5-HT,and 5-HIAA.Conclusion： ECH can reduce the extracellular levels of monoamines and their metabolites in the striatum after cerebral ischemia in rats,which may be one of the anti-ischemic mechanisms.