中文摘要：

目的：研究三七总皂苷（PNS）对快速老化模型小鼠（SAMP8）学习记忆能力及脑内淀粉样前体蛋白（APP）基因转录水平的影响。方法：将SAMP8随机分为PNS高剂量组、PNS低剂量组、石杉碱甲（阳性对照组）组、模型组，各给药组分别按设定剂量灌胃给药，模型组给予等体积双蒸水灌服，连续8W后应用Morris水迷宫、实时逆转录聚合酶链式反应（RT—PCR）的方法，检测PNS高、低剂量组SAMP8学习记忆和脑内APPmRNA含量的影响。结果：PNS能改善SAMP8的学习记忆能力（P〈0．05或P〈0．01），PNS高剂量还能显著降低其脑内APPmRNA含量（P〈0．05）。结论：PNS能显著改善SAMP8的学习记忆能力，其作用途径可能与在转录水平下调APP基因的表达有关。

英文摘要：

Objective ： To study the effect of Panax notoginseng saponins （PNS） on learning and memory ability and APP gene transcription in the brain tissue in senescence accelerated mouse prone 8 （ SAMP8 ）. Methods ： SAMP8 were randomly divided into highdoes PNS group,low-does PNS group, huperzin A group and model group, the treatment groups were treated with the designed drugs re- spectively by intragastric administration for 4 consecutive weeks. The same volume of double distilled water was given to model group. After treatment, the abilities of learning and memory of the mice were tested with morris water maze, the mRNA content of APP was assayed by reverse transcription（RT） and real-time polymerase chain reaction （RT-PCR）. Results：PNS could improve the abilities of learning and memory, high-does PNS could reduce the mRNA content of APP in the brain tissue of SAMPS. Conclusion ： PNS can improve the abilities of learning and memory of SAMPS, the mechanism may be relevant to down-regulating the expression of APP gene at transcriptional level.