β-淀粉样蛋白对D-半乳糖致衰老大鼠学习记忆及海马超微结构的影响  

Effects of β-amyloid on learning-memory and hippocampus neuron ultrastructures in aging rats induced by D-galactose

作　　者：张葳[1] 张昱1 赵晴[2] 杨永梅[1] 

机构地区：[1]吉林大学第一医院神经内科,吉林长春130021 [2]吉林大学中日联谊医院神经内科,吉林长春130031

出　　处：《吉林大学学报（医学版）》2005年第2期246-248,共3页Journal of Jilin University：Medicine Edition

基　　金：科技部国家新药研究基金资助课题 (96 - 90 1- 0 5 - 73)

摘　　要：目的 :观察 β-淀粉样蛋白对 D-半乳糖 (D- gal)致衰老模型大鼠学习记忆能力和海马神经元超微结构的影响。方法 :将水迷宫筛选反应迅速、活跃的 4 8只大鼠随机分为 4组 (n=12 ) ,即生理盐水对照组、 Aβ组、D- gal组和联合模型组 (Aβ+D- gal组 )。生理盐水对照组每天腹腔注射生理盐水 1m L,连续 6周 ,于第 7周双侧海马内注射生理盐水 1μL。 Aβ组第 1～ 6周腹腔注射同生理盐水组 ,于第 7周双侧海马内注射 Aβ 1μL。 D- gal组第 1～ 6周腹腔注射 D- gal 5 0 m g· kg- 1 · d- 1 ,于第 7周双侧海马注射生理盐水 1μL。联合模型组腹腔注射 D- gal5 0 m g· kg- 1· d- 1 ,于第 7周双侧海马内注射 Aβ2 5- 351μL。检测造模前后各组水迷宫逃避潜伏期成绩 ,并用电镜观察海马神经元超微结构的改变。结果 :1造模后 1周 Aβ组、 D- gal组、 D- gal+Aβ组逃避潜伏期较造模前均延长 ,以 D- gal+Aβ组变化最明显 (P<0 .0 1) ,而生理盐水对照组变化不明显。经统计学处理显示 ,造模后 Aβ组、D- gal组、D- gal+Aβ组各组大鼠逃避潜伏期跟造模前及生理盐水对照组比较差异均有显著性 ,Aβ组和 D- gal组与造模前及生理盐水对照组比较差异具有显著性 (P<0 .0 5 ) ,D- gal+Aβ组与造模前及生理盐水对照组比较差异具有?Objective To investigate the effects of β-amyloid on learning memory and hippocampus neuron ultrastructures in aging rats induced by D-galactose (D-gal). Methods Using the water labyrinth test, the rats with quickly reaction were selected and randomly divided into four groups(n=12):control group,Aβ group, D-gal group, and D-gal+Aβ group. In the D-gal group and D-gal+Aβ group, each animal was injected intraperitoneally with the D-gal 50 mg·kg~ -1·d~ -1 for 6 weeks, the decrepitude animal model was established. In the control group and Aβ group, each animal was injected intraperitoneally with same quantity of physiology saline. At the 7th week, the rats in Aβ group and D-gal+Aβ group were injected with Aβ 25-35 into bilateral hippocampal regions, 1 μL in each side; and the rats in control group and D-gal group were injected with same quantity of physiology saline. After the model was established successfully, Morris water maza test was used to determine the ability of learning and memory. Ultrastructures of the hippocampus neurons were observed under electron microscope. Results ①One week after operation, the escape latencies were longer in Aβ group, D-gal group, and Aβ+D-gal group than that in control group (P<0.05),obviously in Aβ+D-gal group (P<0.01). ②The hippocampus neuron ultrastructures in control group were nearly normal, mitochondria cristae of the hippocampus neurons in Aβ group broke. The hippocampus neurons in D-gal group had lipofuscin deposit. In D-gal+Aβ group, nucleuses pyknosis was fonud and chondriosomes swelled. The crista broke and became emptey bubble. Conclusion The combination of D-gal and Aβ can induce a conspicuous reduction of learning-memory ability in rats, and increase the aging degree of brain.

关 键 词：淀粉样Β蛋白 学习 记忆 半乳糖 衰老 阿尔茨海默病 

分 类 号：R-332[医药卫生]