目的 Homer 1a RNA干扰(RNA interference,RNAi)后的Sprague Dawley (SD)大鼠在Morris水迷宫中表现学习记忆能力障碍,本研究旨在通过检测Homer 1a RNAi后大鼠不同脑区亲代谢型谷氨酸受体5(metabotropic glutamate receptor 5,mGluR 5)的表达情况,来初步探讨Homer 1a RNAi致大鼠学习记忆障碍的分子机制。方法 将24只SD大鼠随机分为两组: Homer 1a RNAi组(RNAi组,n=12)和对照组(Nc组,n=12),运用侧脑室注射技术,分别向两组大鼠的侧脑室注射针对Homer 1a 的RNAi慢病毒和无义病毒,等待病毒起效时间7 d,完成相应的行为学检测(Morris水迷宫)后,利用荧光定量PCR 和Western blot 技术检测不同脑组织(前额叶、纹状体、海马)mGluR5 mRNA 和蛋白表达情况。 结果 RNAi组大鼠纹状体和海马mGluR5 mRNA和蛋白表达均较对照组显著降低(纹状体:mRNA t=6.67,蛋白t=3.10;海马:mRNA t=3.08;蛋白t=2.89,P值均<0.05或<0.01),前额叶mGluR5 mRNA和蛋白表达较对照组差异无统计学意义(mRNA t=1.58,蛋白t=1.66,P值均>0.05)。 结论 Homer 1a RNAi后大鼠脑组织Homer 1a相关基因mGluR5表达下调,提示mGluR5可能作为Homer 1a的下游基因,参与Homer 1a RNAi后大鼠学习记忆的损伤过程。
Abstract
Objective Learning and memory abilities of rats were observed damaged in the Morris water maze,after expressions of Homer 1a in their brain interfered by RNA interference (RNA interference,RNAi).Expressions of mGluR 5 in their brain were detected to explore the molecular mechanism of learning and memory impairment after expressions of Homer 1a in their brain interfered by RNAi. Methods 24 Sprague Dawley (SD) rats were randomly divided into two groups:Homer 1a RNAi group (RNAi group,n=12) and control group (Nc group,n=12),and injected into the intracerebroventricular of the rats with Homer 1a RNAi lentivirus or nonsense lentivirus,respectively.Seven days later,completed the behavior tests (Morris Water Maze),mRNA and protein expressions of mGluR5 in some regions (prefrontal cortex,striatum,hippocampus) were analyzed using Quantitative PCR and Western blot. Result mGluR5 mRNA and protein expression in the striatum and hippocampus of RNAi group compared with the control group were significantly lower (striatum:mRNA t=6.67,protein t=3.10;hippocampus:mRNA t=3.08;protein t=2.89,all P<0.05 or <0.01),while there were no significant differences in the prefrontal(mRNA t=1.58,protein t=1.66,all P>0.05). Conclusion Homer 1a RNAi rats exhibit learning and memory impairment,and the expressions of Homer 1a and its related gene mGluR5 are changed,suggesting that mGluR5,as Homer 1a downstream gene,is involved in the mechanisms of learning and memory impairment after expressions of Homer 1a in their brain interfered by RNAi.
关键词
RNA干扰 /
ADHD /
Homer 1a /
亲代谢型谷氨酸受体5 /
学习记忆
Key words
RNA interference /
ADHD /
Homer 1a /
metabotropic glutamate receptor 5 /
learning and memory
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基金
国家自然科学基金(30801255);国家自然科学基金(81250008);江苏省医学重点人才(RC2011022)
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