黄精多糖对慢性脑缺血大鼠学习记忆及脑组织PS-1蛋白表达的影响

The Effects of Polygona-polysaccharose on Learning and Memory and PS-1 Protein Expression of Rats with Chronic Cerebral Hypoperfusion

目的通过观察黄精多糖对慢性脑缺血大鼠学习记忆及脑组织早老素-1(PS-1)蛋白表达的影响,以评价黄精的抗衰老作用及其机制。方法雄性SD大鼠24只,随机分为假手术组、模型组、黄精多糖组、尼莫地平组,每组6只。采用二血管闭塞(2VO)建立慢性脑缺血大鼠模型,给予0.9%氯化钠注射液、黄精多糖、尼莫地平灌胃8周。Morris水迷宫检测大鼠学习记忆能力;尼氏染色检测海马神经元损伤;免疫组织化学法测定前额皮质和海马区PS-1蛋白表达。结果 1)Morris水迷宫实验:黄精多糖组较模型组平均逃避潜伏期缩短(P<0.05),穿台次数增多(P<0.05),黄精多糖组和尼莫地平组之间无显著差异(P>0.05)。2)尼氏染色检测:模型组前额皮质和海马区神经元内尼氏体阳性神经元明显减少,染色较浅,黄精多糖组较模型组尼氏体阳性神经元数目明显增多,与尼莫地平组比较无显著性差异(P>0.05)。3)免疫组化检测:黄精多糖组较模型组大鼠前额皮层、海马区PS-1的蛋白表达减少(P<0.05),黄精多糖组与尼莫地平组比较无显著性差异(P>0.05)。结论黄精多糖能改善慢性脑缺血大鼠的一般行为学评价及组织学变化,减轻细胞结构紊乱,降低慢性脑缺血大鼠前额皮质和海马区PS-1的蛋白表达。

Objective： To evaluate the anti-aging effect of polygona-polysaccharose and its mechanism by observing the effects of Polygona-polysaccharose on learning and memory and PS-1 protein expression of rats with chronic cerebral hypoperfusion. Methods： 24 male SD rats were randomly divided into 4 groups： sham operated group,the model group,Polygona-polysaccharose group,the control group,6 rats in each. 2VO was adopted to establish the rat model of chronic cerebral hypoperfusion,given lavage of 0.9% sodium chloride injection,Polygonapolysaccharose and nimodipine for 8 weeks. The ability of learning and memory was measured with Morris water maze test;hippocampal neuronal damage was detected with the method of Nylon staining;the expression of PS-1in prefrontal cortex and hippocampus was determined by immunohistochemistry. Results： 1）The experimental result of Morris water maze showed that compared with the model group,average escape latency of polygona-polysaccharose group was shortened（P〈 0.05）,and the times of drill increased（P〈 0.05）. There was no significant difference between polygona-polysaccharose group and the control group（P〉 0.05）. 2）Nylon staining showed that in the model group,the positive neurons significantly decreased and the staining was light in prefrontal cortex and hippocampal neurons,while the polygona-polysaccharose group was opposite,and compared with the control group,there was no significant difference（P〉 0.05）. 3）Immunohistochemical detection showed that compared with the model group,PS-1 protein expression in prefrontal cortex and hippocampus of rat reduced in polygona-polysaccharose group（P〈 0.05）. There was no significant difference between polygona-polysaccharose group and the control group（P〉 0.05）. Conclusion： Polygona-polysaccharose can improve the general behavioral assessment and histological changes,decrease cell structure disorder,and reduce PS-1 protein expression in prefrontal cortex and hippocampus of rats with chronic cerebral hypoperfusion.