深低温低流量Akt1^(+/-)转基因小鼠模型的构建与表型分析  

Construction of Akt1^(+/-) transgenic animal model of deep hypothermic low flow andphenotype analysis

作　　者：马志飞[1] 莫绪明[1] 杨中洲[2] 顾群[1] 陈凤[1] 何晓敏[1] 张永生[1] 束亚琴[1] 

机构地区：[1]南京医科大学附属南京儿童医院,210008 [2]南京大学模式动物研究所

出　　处：《江苏医药》2010年第8期909-912,共4页Jiangsu Medical Journal

基　　金：国家自然科学基金(30772156)

摘　　要：目的构建模拟深低温低流量过程的Akt1部分敲除(Akt1+/-)的转基因小鼠模型,并分析小鼠的表型。方法3周龄Akt1+/-转基因小鼠与野生型(WT)小鼠各为48只,分别随机均分为脑部血流量的监测(A)组、血液动力学参数指标监测(B)组、缺血再灌注后RT-PCR实验(C)组与蛋白电泳实验(D)组,每组再分为假手术组与手术组2个亚组。每个亚组6只。通过在(18.5±0.5)℃的低温下钳闭转基因与野生型小鼠颈总动脉2h,并重新开放,模拟深低温低流量的病理生理过程。检测小鼠血流动力学的变化与脑部的血流情况,统计小鼠死亡率,通过RT-PCR和Westernblot等分析小鼠表型。结果阻断颈总动脉后,激光多普勒血流仪测定脑部血流量减少86%以上;Akt1+/-小鼠再灌注24h后的Akt下游线粒体凋亡通路中的细胞色素C与Caspase-3表达水平以及死亡率较假手术对照组增加(P<0.05);转基因小鼠的Akt活性被抑制。结论这一转基因小鼠模型基本模拟了深低温低流量的临床病理生理。Akt1部分敲除后,加重了小鼠的脑损害程度,说明PI3K/Akt信号通路具有脑保护功能。Objective Construction of Akt1＋/-transgenic animal model of deep hypothermic low flow（DHLF）and investigate the phenotype of the animal model.Methods The Akt1＋/-transgenic mice（n=48）and wild type of C57BL/6 mice（n=48）were divided into 4 groups underwent gradual hypothermia of（18.5±0.5）℃.Each group was divided into two subgroups of cerebral ischemia-reperfusion（I-R）（bilateral common carotid arteries were occluded for 120 min and reperfused and rewarmed afterwards）and sham-operation as the control with 6 mice each.Regional cerebral blood flow（rCBF）was determined by laser Doppler flowmetry（LDF）.Apoptosis of cerebral cells and different isforms of AKT were examined.Results rCBF was significantly decreased by 86% or more after cerebral ischemia.Cytochrome C,Caspase-3 expression and mortality were higher in I-R subgroup than those in sham-operation subgroup at 24h after reperfusion（P0.05）.The Akt activity of Akt1 mutant mice was depressed.Conclusion The Akt1＋/-transgenic animal model of deep hypothermic low flow was constructed.The cerebral injury was enhanced by partially knocking down Akt1 after DHLF procedure,indicating that PI3K/Akt signal pathway has cerebral protective efficiency.

关 键 词：低温 脑保护 Akt1+/-转基因 动物模型 

分 类 号：R726[医药卫生—儿科]