远志皂苷对AD小鼠学习记忆能力及中枢胆碱能系统标志酶活性的影响

The influence of tenuigenin on learning-memory and the activity of marker enzymes of central cholinergic system in AD mice

目的:建立能模拟人类Alzheimer病(AD)的小鼠病理模型,并观察远志皂苷对AD小鼠学习记忆及胆碱能系统标志酶活性的影响。方法:小鼠单侧海马区注射凝聚态Aβ1-40制备AD小鼠模型,运用Morris水迷宫检测各组小鼠学习记忆能力,采用生化法检测各组小鼠脑组织匀浆中AchE活性变化,采用HE染色观察小鼠脑组织的病理变化,采用免疫组织化学方法观察小鼠脑组织ChAT表达的变化。结果:与模型组相比,中、高剂量(74 mg/kg、148 mg/kg)远志皂苷干预治疗组小鼠逃逸潜伏期明显缩短,穿越平台次数明显增多,海马、皮层神经细胞凋亡减少,同时脑内AchE活性降低,ChAT阳性表达增加。结论:远志皂苷能改善AD小鼠的学习记忆能力,其作用机制可能与保护中枢胆碱能系统功能有关。

Objective：To establish a mouse pathological model that can simulate human Alzheimer’s disease（AD）,and to observe the effects of tenuigenin on learning-memory and the activity of marker enzymes of central cholinergic system in this model.Methods ： The AD mouse model was established by injection of pre-aggregated Aβl-40 into the unilateral hippocampus,then learning and memory ability were determined by Morris water maze,the activity of AchE were measured by biochemical methods in the different groups of mice brain tissues,pathological change were examined through HE staining,the expression of ChAT were assessed by immunohistochemistry.Results ： Compared with the model group,The average escape latency were obviously shortened and the crossing times increased significantly in the Morris water maze,the neurons death were reduced in the cortex and hippocampus,the activity of AchE decreased and the expression of ChAT were increased in treatment groups（P〈0.01,P〈0.05）.Conclusion ：TEN can improve the learning-memory in AD mice,and its mechanism may be related to protection of central cholinergic system function.