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目的:探讨纹状体细胞外液中多巴胺(DA)及其代谢产物在电针抗脑缺血再灌注损伤中的作用.方法:将50只雄性SD大鼠随机分为正常组、假手术组、假手术+电针组、模型组、模型+电针组.用右侧大脑中动脉阻塞方法制成脑缺血再灌注模型.电针各组电针“风池”20 min后,休息10 min,再电针20 min.通过微透析及高效液相色谱技术测定大鼠纹状体细胞外液中DA及其代谢产物3,4-二羟基苯乙酸(DOPAC)、高香草酸(HVA)的浓度.结果:在实验过程中,正常组、假手术组、假手术+电针组纹状体内胞外DA、DOPAC、HVA含量无明显变化.在脑缺血后30 min以及再灌注后15 min,DA含量出现两次明显升高(P<0.05),再灌注后120 min也观测到1次上升的趋势;而DOPAC含量在缺血后15 min、75 min以及再灌注后75 min出现3次高峰(P<0.05).经电针治疗后,DA含量于再灌注后90 min、120 min明显低于模型组(P<0.05);而DOPAC含量在再灌注后维持在基础水平,未出现第3次高峰.HVA的变化趋势与DOPAC相似,经电针治疗后HVA含量于再灌注75 min明显低于模型组.结论:电针可减少脑缺血再灌注后大鼠纹状体内细胞外液中DA及其代谢产物的蓄积,发挥脑保护作用.“,”Objective To explore the involvement of dopamine (DA) and its metabolites in the extracellular fluid of the striatum on the resisting action of electroacupuncture (EA) for acute cerebral ischemia-reperfusion (Cl/R) injury. Methods A total of 50 SD male rats were randomly divided into normal control, sham-operation (sham), sham+ EA, Cl/R model, CI/R+ EA groups. Cl/R model was induced by right middle cerebral artery occlusion (MCAO) for 90 min and reperfusion for 225 min. EA (2 Hz, 3 mA, continuous waves) was applied to“Fengchi” (GB 20) for 20 min, with a 10 min rest, and given once again for 20 min. The concentrations of DA and its metabolites [3,4- dihydroxy-phenyl acetic acid (DOPAC) and homovanillic acid (HVA)] in the extracellular fluid of the striatum were determined by microdialysis and high performance liquid chromatography (HPLC). Results The extracellular levels of DA, DOPAC and HVA in normal group, sham group and sham+ EA group had no significant changes during the whole study. The extracellular level of DA peaked 15-45 min after Cl and 0-30 min after Cl/R (P<0. 05). A rising trend was also observed 120 min following Cl/R. DOPAC level peaked 15 min and 75 min after Cl and 75 min after Cl/R. After EA, DA level was significantly lower in EA group than that in model group 90 min after Cl/R (P<0. 05), and no peak was observed again. After EA, DOPAC level maintained its basic level, and no peak was found after Cl/R. The changing trend of HVA was similar to that of DOPAC, and the extracellular HVA level in EA+model group was significantly lower than that in model group 75 min after Cl/R. Conclusion EA can decrease the accumulation of DA and its metabolites in the extracellular fluid of the stri-atum, which may contribute to its effect in preventing the brain from Cl/R injury.