急性脑老化模型大鼠脑神经元中衰老基因p21^(WAF-1)的表达  

Expression of P21^(WAF-1) of Neuron in Second-actue Brain Aging Models

作　　者：孙茂民[1] 刘珺[1] 陈尔齐[1] 江家贵[2] 

机构地区：[1]苏州大学 医学院细胞神经生物学研究室,苏州215123 [2]苏州大学 放射医学与公共卫生学院,苏州215123

出　　处：《实验动物与比较医学》2006年第4期223-226,共4页Laboratory Animal and Comparative Medicine

基　　金：苏州大学青年基金(Q3134045)

摘　　要：目的探讨急性脑老化模型脑组织中衰老基因p21^(WAF-1)的表达,为研究脑老化的发生机制及临床防治提供理论依据。方法以^(60)Co照射SD大鼠建立急性脑老化模型(简称模型组),5月龄SD大鼠作为对照组；通过Y型迷宫测定大鼠的学习与记忆能力,检测大鼠外周血超氧化物岐化酶SOD(抗氧化能力)和丙二醛MDA(脂质过氧化能力)来评判建模是否成功；通过原位核酸杂交检测鼠脑各部位神经元p21^(WAF-1)的表达。结果Y型迷宫测定表明,模型组大鼠的学习和记忆能力明显下降,与对照组相比差异显著；模型组外周血中SOD明显降低,而MDA则显著升高；模型组大鼠脑内p21^(WAF-1)的表达以海马、皮质表达最高,其次是下丘脑和纹状体,小脑表达最低；而正常对照组神经细胞p21的表达在小脑呈阴性,其他脑区有表达,但阳性率及强度较弱,与模型组相比有显著差异。结论脑组织海马和皮质等神经元对自由基攻击非常敏感,神经元中p21^(WAF-1)的表达增高,可能是参与神经元的DNA的损伤修复,并抑制神经元的凋亡。Objective To investigate the expression of p21^WAF-1 in brain tissue of the acute brain aging rat models, which will provide theory for brain-aging mechanism and clinic prevention and therapy. Methods The rat acute brain-aging model was established by ^60Co radiation, and 5-monthly SD rats as the control group. The learning and memory of rats ability was determined by Y type labyrinth, and the antioxidant and lipid peroxidative injury of rats were measured by SOD and MDA in blood. With the in situ hybridization, the expression of p21^WAF-1 in hippocampal neuron was measured. Results The learning and memory ability of brain aging rat was decreased with Y type labyrinth. The blood＇s SOD in brainaging model was significantly lower than that of the control, the blood＇s MDA in brain-aging model was markedly higher than that of the control. Over expression of p21^WAF-1 was found in hippocampus, cortex, in hypothalamus and corpus striatum secondly, and in cerebellum est, the expression of p21^WAF-1 were found in cone cells of cortex and hippocampus, in purkinje cells of cerebellum; the expression of p21^WAF-1 were negative in cerebellum of control group, and the expressions of p21^WAF-1 were found in other different brain regions in control group, but lower and weaker. Conclusions The simple and easy acute brain-aging model was established. Over expression of p21^WAF-1 may maintain the character of senile neuron.

关 键 词：脑老化 模型 电离辐射 p21^WAF-1 大鼠 

分 类 号：R741[医药卫生—神经病学与精神病学]