中文摘要：

目的探索高脂饮食对大鼠学习记忆功能、海马神经元数量、树突形态的影响。方法雄性成年sD大鼠24只，随机数字表法分为高脂饮食组（n=12）和对照组（n=12），高脂饮食组的大鼠喂食12周的高脂饲料，对照组喂食标准动物饲料。通过Morris水迷宫及物体辨别实验等评估大鼠学习记忆功能，旷场实验评估运动功能及焦虑样症状，高尔基染色检测海马神经元树突棘密度的改变，尼氏染色观察海马神经元数量及病理学变化。结果高脂饮食导致大鼠空间学习能力受损，表现为逃避潜伏期[第1～5天：（38．50±9．70）s、（20．08±7．35）s、（19．96±10．56）S、（22．75±12．51）s、（14．56±4．82）s]，明显长于对照组[第1～5天：（33．61±12．41）s、（14．25±7．89）s、（15．06±7．59）S、（5．53±2．81）s、（4．70±1．58）s]；空间记忆能力受损，表现为到达原平台潜伏期[（30．46±21．43）s]长于对照组[（5．18±1．33）S]；工作记忆能力受损，表现为逃避潜伏期明显长于对照组（P〈0．05）；物体辨别记忆受损，表现为辨别指数低于对照组[（0．67±0．12）vs（0．81±0．08）]，差异具有统计学意义（P=0．038）；未出现焦虑样症状（均P〉0．05）；海马神经元数量、树突棘密度均低于对照组[分别为（209．73±24．29）个／mmvs（262．2±18．94）个／mm，（17．9±2．84）个／20μmvs（21．93±2．56）个／20μm]，差异具有统计学意义（P〈0．05）。结论高脂饮食的摄入可以导致大鼠学习记忆功能下降，同时损伤大鼠海马神经元数量及树突棘密度。

英文摘要：

Objective To explore the influence of high fat diet on learning and memory,as well as the al- teration of the number of neurons and morphology of dendritic spines in rat hippocampi. Methods 24 male adult SD rats were randomly assigned to high fat diet group or control group. The rats were fed with high-fat diet or stand- ard laboratory rodent chow diet for 12 weeks. Learning and memory were tested by Morris water maze and object recognition tests ,and mood and motor ability were tested by open field tests.Golgi staining detected dendritic spine density of hippocampal neurons, and Nissl staining was used to observe the number of hippocampal neurons and pathological changes. Results High-fat diet induced rat spatial learning deficits, which was demonstrated by the prolonged escape latency （ （38.50±9.70） s, （ 20.08±7.35 ） s, （ 19.96± 10.56） s, （ 22.75± 12.51 ） s, （14.56±4.82） s） compared with the control （（33.61±12.41） s, （14.25±7.89） s, （15.06±7.59） s, （5.53±2.81） s, （4.7±1.58） s）. The spatial memory deficits demonstrated that the latency reaching platform （ （ 30.46 ± 21.43 ） s ） was prolonged compared with control （（ 5.18± 1.33 ）s）.The working memory was impaired, which was demonstrated by the pro- longed escape latency compared with control group （P〈 0.05 ）. Discrimination index lowered than control group （ （ 0.67 ± 0.12） vs （ 0.81 ± 0.08 ） ）, and the difference was significant （P= 0.038 ）, but no anxiety behaviors were ob- served（P= 0.461 ）.The neuron number of hippocampal neurons and dendritic spine density were significantly low- ered than those in the control group（（209.73±24.29） vs （262.2±18.94） ,（17.9±2.84） vs （21.93±2.56）,respec- tively） （P〈0.05）. Conclusion Intake of high-fat diet can impair learning and memory in rats, as well as decrease the number of neurons and the density of dendritic spines in the hippocampus.