PTEN表达下调对神经元缺氧损伤的保护及其作用机制  

Neuroprotective effect of PTEN down-regulation on neuron subjected to anoxic insult

作　　者：陈力学[1] 姜利人[2] 刘宝松[2] 龙在云[2] 康格非[1] 

机构地区：[1]重庆医科大学附属第一医院二病区实验室,重庆400016 [2]第三军医大学大坪医院野战外科研究所第三研究室,创伤,烧伤与复合伤国家重点实验室,重庆400042

出　　处：《第三军医大学学报》2006年第19期1942-1944,共3页Journal of Third Military Medical University

基　　金：重庆市科委应用基础研究资助项目(2003-8107)~~

摘　　要：目的探讨PTEN对NR2B磷酸化的调节作用及其在阻断Ca2+内流和神经元保护中的作用。方法建立神经元缺氧缺糖(oxygen-glucose deprivation,OGD)损伤模型,转染shRNAspten-GFP质粒,采用Fura 2-AM法测定胞内Ca2+浓度,用免疫沉淀法和W estern b lotting检测NR2B及磷酸化水平。结果OGD后NR2B酪氨酸磷酸化水平和胞内Ca2+浓度显著升高,shRNAspten-GFP能成功转染到神经元中,并可显著下调其酪氨酸磷酸化水平(F=11.82,P<0.05),胞内Ca2+浓度也显著低于损伤组和PshGFP阴性对照组(F=62.85,P<0.05)。结论PTEN表达下调对缺氧诱导的NR2B酪氨酸磷酸化水平升高有拮抗作用,阻断Ca2+内流,从而达到神经元保护作用。Objective To investigate the regulation of PTEN on NR2B phosphorylation and the active roles in blocking Ca^2＋ influx and neuroprotection. Methods In the oxygen-glucose deprivation （OGD） model with anaerobic gas mixture and deoxygenated, glucose-free extracellular solution, shRNAspten-GFP and unrelated control plasmid PshGFP transfection were done respectively. Intracellular free calcium concentration were measured with Fura-2 AM fluorescent indicator, the expression of NMDA receptor subunits NR2B and its tyrosine phosphorylation were analyzed by immunoblotting and immunoprecipitation （IP）. Results shRNAspten-GFP plasmid could been expressed successfully in cultured neurons. Tyrosine phosphorylation levels of NMDA receptor subunits NR2B after OGD decreased significantly after shRNApten treatment （F = 11.82, P 〈0.05 ）. Intracellular free calcium concentration with shRNAspten-GFP treatment after OGD was significantly lower than that in OGD group and PshGFP group （F = 62.85, P 〈 0.05）. Conclusion PTEN down-regulation could effectively suppress the tyrosine phosphorylation of NR2B induced by OGD and the followed increase of intracellular free calcium concentration, and then protect neuron from anoxic injury.

关 键 词：PTEN NR2B shRNAs 酪氨酸磷酸化 

分 类 号：R338.1[医药卫生—人体生理学] R394.2[医药卫生—基础医学]