老年性痴呆模型大鼠学习记忆功能障碍的实验探讨

目的:探索D-半乳糖-Aβ复合模型大鼠学习记忆功能的改变,研究老年性痴呆(AD)的发病机制.方法:(1)采用1.25%D-半乳糖腹腔注射(50mg/kg·d,连续6周)致衰老,结合双侧海马齿状回背侧注射10g/1μL凝聚态β-淀粉样肽1-40(β-amyloid peptide,Aβ1-40)的复合造模方法,拟建立AD样学习记忆功能障碍的动物模型.实验动物随机分成3组:AD模型组、假造模对照组和正常对照组.(2)以单位时间逃避潜伏期(s/3min)及其逃生错误频率(次/3min)为观察指标,进行水迷宫行为学试验测定大鼠学习记忆功能的改变.结果:AD大鼠安全逃避潜伏期明显延长,逃生错误频率高,与两对照组比较差异有统计学意义(P<0.01).结论:D-半乳糖-A复合造模致AD大鼠模型具有较好的老年性痴呆的仿真特性.水迷宫行为学试验能准确反映动物学习记忆功能.

Learning and Memory Impairment of Model Rat of Aging-dementia

Objective:To explore on learning and memory impairment of model rats induced by D-galactos and Aβ 1-40,for mechanism of aging-dementia(AD).Methods:(1) With 1.25 % D-galactose(50mg/kg·d,6 weeks) injected into abdominal cavity and incubated β-amyloid peptide protein 1-40(Aβ 1-40) injected bilaterally into the dorsal lateral of the dentate gyrus in the hippocampus of rats,AD-like aminal model on learning and memory impairment was established.The experi-mental animals were devided randomly into three groups:AD model group,false model group and normal control group.(2) Using a water-maze test,escape latency and frequency of escape failure were used as the index to assess learning and memory function of rats.Results:Escape latency of AD model rats was obviously prolonged(22.87:9.38 s /3 min),and frequency of escape failure was increased significantly(6.50:1.94 times /3 min) as compared with two control groups(P < 0.01).Conclusion:Learning and memory impairment of AD-like rat models induced by D-galactos and Aβ 1-40 have preferably characters of aging-dementia.The water-maze test can assess accurately the learning and memory function of rats.