中文摘要：

目的：观察人参皂苷Rgl联合美满霉素对脑缺血大鼠学习与记忆的影响和海马NMDA受体亚单位（NR2A／B）表达的变化。方法：本研究将48只成年雄性sD大鼠分为正常组、假手术组、慢性脑缺血组、人参皂苷Rgl＋美满霉素处理组，每组12只。利用双侧颈总动脉结扎方法制备慢性脑缺血再灌注大鼠模型，造模后药物处理21d，采用Morris水迷宫和及穿梭箱实验测试其学习与记忆成绩，再采用Western Blot方法分析海马的NR2A，NR2B的表达。结果：Morris水迷宫测试结果显示模型组大鼠寻找平台的潜伏期较假手术组明显延长，药物处理组大鼠寻找平台的潜伏期较模型组明显缩短；穿梭箱测试结果显示：与假手术组相比，模型组大鼠电击时间明显延长；与模型组相比，治疗组大鼠电击时间明显缩短；Western Blot结果显示：模型组NR2A表达水平较假手术组明显降低，而NR2B明显升高；药物处理组大鼠海马内NR2A表达水平较模型组明显上调，而NR2B明显下调。结论：人参皂苷Rgl联合美满霉素明显改善脑缺血大鼠的学习记忆能力，其作用机制可能与调节NMDA受体表达有关。

英文摘要：

Objective： To investigate the effects of minocycline and ginsenoside Rgl on learning and memory of chronic cerebral hypoperfusion rats and the variation of the expression of NMDA receptor subunit NR2A and NR2B in the hippo- campus. Methods： Forty eight normal male SD rats were randomly divided into control group, sham group （ Sham ） , chronic cerebral hypoperfusion group （CCH）, ginsenoside and minocycline treatment group （GMT）. The model was es- tablished by ligating common carotid artery. After modeling, the rats were administrated with minocycline and ginsenoside Rgl for 21d. Learning and memory ability was evaluated with Morris water maze and shuttle box, then the expression of NR2A and NR2B in hippocampus was analyzed with western blot. Results： Morris water maze result show： compared tosham group, the latency to find platform was significantly increased in model group rats. Compared to model group, the latency to find platform was significantly reduced in treatment group. Shuttle box result show ： the shock time of the model group rats was much higher than rats in sham group. The shock time of the treatment group rats was much lower than rats in model group. Compared to sham group, the expression of NR2A in the hippocampus was significantly down-regulated, the expression of NR2B in the hippocampus was significantly up-regulated. Compared to model group, the expression of NP,.2A was significantly up- regulated and the expression of NR2B was significantly down-regulated in treatment group. Conclusion： These results indicated that ginsenoside Rgl and minocycline treatment enhanced the learning and memory a- bility of chronic cerebral hypoperfusion rats, and the variation of the expression of NMDA receptors in the hippocampus might be one of the mechanisms that influence the learning and memory ability.