中文摘要：

[目的]观察黄芪多糖对血管性痴呆大鼠学习记忆能力的影响，并探讨其机制．[方法]用两侧颈总动脉永久性结扎法制作血管性痴呆大鼠模型，并随机分成对照组和黄芪多糖组．两组分别灌胃给予生理盐水和黄芪多糖水溶液30d后，利用脑部微量透析法和高效液相色谱法测定大鼠海马区细胞外液中的天冬氨酸、谷氨酸、谷氨酰胺、甘氨酸及牛磺酸水平，并进行Morris水迷宫实验．[结果]与对照组相比较，黄芪多糖组的逃避潜伏期明显缩短（P〈O．05），穿越原站台区次数明显增加，而且海马区谷氨酸、谷氨酰胺、牛磺酸及甘氨酸水平均显著降低（P〈0．05）．[结论]黄芪多糖增强血管性痴呆模型大鼠空间学习记忆能力，其作用机制可能与降低海马区几种氨基酸物质水平有关．

英文摘要：

OBJECTIVE To study the effects of astragalus polysaccharides （APS） on spatial learning and memory in rats with vascular dementia （VD）. METHODS Rats model with ~D were established by permanent ligation of bilateral common carotid artery, and then randomly divided into control and APS groups. The rats were performed by intragastric administration with APS and saline for 30 d, and then the extracellular concentrations of aspartic acid（Asp）, glutamate （Glu）, glutamine （Gln）, glycine （Gly） and taurine （Tau） in the hippocampus were measured by microdialysis and high performance liquid chromatography （HPLC） as well as the Morris water maze test was performed. RESULTS As compared with control group, the APS group showed significantly shorter escape latency to locate the hidden platform and more number of crossing over the previous platform site（P~0.05）, and the extracellular concentrations of Glu, Gin, Tau and Gly in the hippocampus were significantly decreased in APS group（P%0.05）. CONCLUSION ASP enhance the ability of spatial learning and memory in rats with VD, and its mechanism maybe related to decrease in amino acids concentrations in the hippocampus.