乙酰胆碱特征超低频经颅磁刺激对阿尔茨海默病模型大鼠记忆力的影响

目的探索乙酰胆碱特征超低频经颅磁刺激(ACh-TMS)对阿尔茨海默病(AD)模型大鼠学习记忆力的影响及其机制。方法 SD大鼠随机分为正常组(N组)、模型组(M组)、假手术组(P组)、假刺激组(M+P组)、乙酰胆碱特征超低频磁刺激组(ACh-TMS组)和多奈哌齐组(donepezil组),每组10只。双侧海马注射Aβ1-42建立AD模型。Morris水迷宫实验观察大鼠学习记忆力。检测海马组织脑源性神经营养因子(BDNF)及乙酰胆碱(ACh)含量、乙酰胆碱酯酶(AChE)及胆碱乙酰转移酶(Ch AT)活力变化。改良Highman刚果红法观察淀粉样物质沉积情况。结果与M+P组比较,ACh-TMS组大鼠平均逃避潜伏期缩短、目标象限游泳时间百分比及跨越平台次数明显增多(P0.05);BDNF、ACh含量及Ch AT活力显著提高(P0.05)。除N组和P组外,其余各组大鼠海马区可见淀粉样物质沉积。结论 ACh-TMS可改善AD模型大鼠学习记忆力,其机制可能与提高中枢胆碱能递质含量、促进海马BDNF表达有关。

Effect of acetylcholine characteristic ultra-low frequency transcranial magnetic stimulation on spatial learning and memory function in rats with Alzheimer's disease

Objective To investigate the effect of acetylcholine characteristic ultra-low frequency transcranial magnetic stimulation (ACh-TMS) on spatial learning and memory function in rats with Alzheimer's disease (AD) and possible mechanisms.Methods Sprague-Dawley rats were randomly divided into normal (N) group,model (M) group,sham-operation group (P group),sham-stimulation group (M + P group),ACh-TMS group,and donepezil group,with 10 rats in each group.A rat model of AD was established by injection of Aβ1-42 at the bilateral hippocampus.The Morris water maze test was used to evaluate the spatial learning and memory function of all rats.The levels of brain-derived neurotrophic factor (BDNF) and acetylcholine (ACh) were measured,as well as the changes in the activities of acetylcholinesterase (AChE) and choline acetyltransferase (ChAT) in the hippocampus.The modified Highman Congo red staining was used to observe the deposition of amyloid substances in the hippocampus.Results Compared with the M + P group,the ACh-TMS group had a significantly shorter mean escape latency and significant increases in the swimming time percentage in target quadrant and number of platform crossings (P ＜ 0.05),as well as significant increases in the content of BD-NF and ACh and the activity of ChAT (P ＜ 0.05).All groups except the N and P groups showed the deposition of amyloid substances in the hippocampus.Conclusions ACh-TMS may improve the spatial learning and memory function of AD rats,possibly by increasing the content of cholinergic transmitters in the central nervous system and upregulating the expression of BDNF in the hippocampus.