国际麻醉学与复苏杂志   2013, Issue (5): 8-8
    
APPswe/PS1dE9双转基因小鼠肝叶部分切除术后认知功能变化及海马Cdk5/p25的表达
许方方, 徐静, 万燕杰1()
1.徐州医学院
The change of cognitive function and the expression of Cdk5/p25 in hippocampus in APPswe/PS1dE9 double transgenic mouse after partial hepatectomy
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摘要：

目的 观察肝叶部分切除术后APPswe/PS1dE9双转基因阿尔茨海默病模型小鼠认知功能的变化,探讨其与海马Cdk5/p25表达的关系。方法 实验采用3月龄APPswe/PS1dE9双转基因小鼠（TG）（168只）以及野生型小鼠（WT）(12只),TG小鼠采用随机数字表法随机分为3组（每组56只）：对照组、麻醉组和手术组。通过Morris水迷宫连续训练5 d并检测术后1 d~7 d学习记忆能力。采用免疫组织化学法及Westernblot法对术后12 h、1、3、7 d小鼠海马内细胞周期蛋白依赖性蛋白激酶5 (cyclin-dependent kinase 5, Cdk5)、p35和p25蛋白的表达进行检测。 结果 通过Morris水迷宫训练,3月龄TG小鼠学习记忆能力与WT野生型小鼠相比较，差异无统计学意义(P＞0.05)。肝叶部分切除术后,手术组术后1 d~7 d逃避潜伏期[1 d:(28.46±3.29) s,2 d:(31.64±4.23) s,3 d:(38.11±4.01) s,4 d:(41.63±5.73) s,5 d:(47.82±5.22) s,6 d:(51.13±3.83) s,7 d:(55.81±7.34) s]，较对照组[1 d:(26.93±4.28) s,2 d:(27.29±4.50) s,3 d:(29.56±5.44) s,4 d:(30.29±2.29) s,5 d:(31.15±6.14) s,6 d:(29.07±3.90) s,7 d:(28.83±3.20) s]和麻醉组[1 d:(27.01±1.68) s,2 d:(30.48±2.61) s,3 d:(31.47±4.40) s,4 d(32.32±4.61) s, 5 d:(30.60±3.54) s,6 d:(32.26±5.04) s,7 d:(34.22±3.31) s]明显延长(P＜0.05)。免疫组织化学结果显示:手术组术后1、3、7 d Cdk5在海马CA1区的积分光密度值[1 d:(312 298.71±33 602.17),3 d:(318 515.54±39 982.50),7 d:(334 206.11±40 182.03)], 较对照组[1 d:(192 647.79±17 024.88),3 d:(230 372.90±14 129.65),7 d:(222 318.13±23 843.41)]和麻醉组[1 d:(201 881.17±14 636.61),3 d:(232 366.42± 20 693.85),7 d:(250 145.87±23 890.17)]明显增高(P＜0.05)。Western blot检测结果显示:与对照组和麻醉组比较,手术组术后1、3、7 d海马内Cdk5灰度值[1 d:(0.48±0.07),3 d:(0.46±0.03),7 d:(0.48±0.11)和p25灰度值[1 d:(0.025±0.003),3 d:(0.023±0.003),7 d:(0.022±0.006)]逐渐增高,差异有统计学意义(P＜0.01),而p35表达未发生显著变化。 结论 肝叶部分切除术可能加速APPswe/PS1dE9双转基因小鼠学习记忆能力下降,使其提前进入临床期,其机制可能与海马内Cdk5和p25表达的上调有关。
关键词： 术后认知功能障碍；阿尔茨海默病；细胞周期蛋白依赖性蛋白激酶5；p25
Abstract:

Objective　 To observe the relationship between the expressions of cyclin-dependent kinase 5（Cdk5） in hippocampus and the change of cognitive function in APPswe/PS1dE9 double transgenic model of Alzheimer disease（AD） mouse after partial hepatectomy. Methods 3-month-old APPswe/PS1dE9 double transgenic gene mouse (TG) (n=168) and littermate wild-type mouse (WT) (n=12) were observed in this study. TG mice were randomly divided into control group, anesthesia group and surgery group. Learning and memory abilities at d1-d7 after partial hepatectomy were detected after 5 d Morris water maze trained for mice. The changes of Cdk5, p35 and p25 in hippocampus were measured by immunocytochemistry and Western blot at 12 h, 1, 3 d and 7 d after partial hepatectomy. Results There was no significant difference between TG and WT in learning and memory ability. Compared with the control group [1 d: (26.93±4.28) s, 2 d:(27.29±4.50) s, 3 d:(29.56±5.44) s, 4 d:(30.29±2.29) s, 5 d:(31.15±6.14) s, 6 d:(29.07±3.90) s, 7 d:(28.83±3.20) s] and anesthesia group [1 d:(27.01±1.68) s, 2 d:(30.48±2.61) s, 3 d:(31.47±4.40) s, 4 d:(32.32±4.61) s, 5 d:(30.60±3.54) s,6 d:(32.26±5.04) s,7 d:(34.22±3.31) s], the escape latency of surgery group [1 d:(28.46±3.29) s, 2 d:(31.64±4.23) s, 3 d:(38.11±4.01) s, 4 d:(41.63±5.73) s, 5 d:(47.82±5.22) s, 6 d:(51.13±3.83) s, 7 d:(55.81±7.34) s] were significantly longer at d1-d7 after partial hepatectomy (P<0.05). The immunochemistry staining of brain slice showed that the expressions of Cdk5 in surgery group markedly increased, and IOD value were （312 298.71±33 602.17）,（318 515.54±39 982.50） and （334 206.11±40 182.03）at d1, d3, d7, respectively (P<0.01). Western blot showed that p25 was upregulated in time-dependent manner in surgery group (P<0.01), while the level of p35 expression did not change significantly. Conclusions Partial hepatectomy accelerate the decline of learning and memory ability in APPswe/PS1dE9 double transgenic mouse, which mechanism may be related to the upregulation of Cdk5 and p25 in hippocampus.
Key words: Postoperative cognitive dysfunction; Alzheimer disease; Cyclin-dependent kinase 5; p25