摘要
背景:通过竞争性抑制一氧化氮合酶(nitricoxidesynthase,NOS),可损害大鼠的学习记忆行为,表明NO/NOS对维持正常的学习记忆功能是必需的,但有关学习记忆障碍时NOS神经元的变化尚不十分清楚。目的:探讨NOS神经元与学习记忆障碍的关系。设计:完全随机设计,对照实验研究。地点和材料:本研究地点为中南大学湘雅医学院人体解剖学和神经生物学系,材料为健康昆明雄性小鼠32只,6～8周龄,体质量20～25g,购于湖南医科大学动物学部。干预:32只小鼠随机分为模型组和对照组,每组各取7d和14d两个时间点,每个时间点各8只小鼠。采用辐射式三等份Y型迷宫测试装置,检测动物的空间辨别性学习记忆能力。应用免疫组化结合组织化学方法显示学习记忆障碍小鼠脑中NOS神经元的变化。主要观察指标:检测动物的空间辨别性学习记忆能力,观察切片NOS神经元形态并计数。结果:随训练次数的增加,对照组小鼠在Y型迷宫中的正确次数逐渐增加(术前第1天8.3±1.2,术后第7天10.1±1.0),而模型组小鼠术后在Y型迷宫测试中的正确次数较术前(8.3±1.2)明显减少(术后第7天4.7±2.4,P<0.05),与对照组同时间点相比,差异有显著性意义(P<0.01)。但术后14d模型组小鼠在迷宫测试中的正确次数渐有增加(9.3±0.7)。
BACKGROUND:Learning and memory impairment can be induced in rat model by compe titively inhibitting the activity of nitric oxide synthase(NOS),indicating that NO/NOS was crucial for normal learning and memory.However,changes of NOS neuron related to cognitive impairment still remained unclear. OBJECTIVE:To explore the correlation of NOS neuron with learning and memory im pairment. DESIGN:Completely randomized controlled trial. SETTING and MATERIALS:This trial was carried out at the Department of Human Aa natomy and Neurobiology of Xiangya Medical College of Central South University.T hirty-two healthy male Kunming mice(6-8 years of age,weighing 20-25 g) were p urchased from the Experimental Animal Center of Hunan Medical College. INTERVENTION:All mice were randomly divided into model group and control group ,which were further divided according to time points(7 days,14 days) into two su bgroups respectively with eight mice in each subgroup. Each mouse's spatial diff erentiation memory was tested with radiation trisection Y-type maze.Meanwhile,i mmunohistochamical method was used to observe changes of cerebral NOS neurons in mice with cognitive impairment. MAIN OUTCOME MEASURES:Spatial differentiation memory and morphology and counti ng of NOS neurons. RESULTS:With the increase of training times, mice in the control group showed more exactness in Y-type maze test(8.3±1.2 at 1 day pre-operatively vs 10.1± 1.0 at 7 days post-operatively),while reverse changes were found in model mice presented by the exactness of pre-operation(8.3±1.2)significantly decreased to 4.7±2.4 at 7 days post-operatively(P< 0.05),which was significantly differe nt from that in the control group at the corresponding time points(P< 0.01).But model rat showed increased exactness at 14 days after operation(9.3±0.7).Appa rently decreased NOS neurons were found in hippocampus CA1-4 regions of mice wi th cognitive impairment,and a large number of new NOS neurons appeared in granul ar cell layers of dentate gyri and extracortex of pearform region. CONCLUSION:NOS neuron in hippocampus is crucial for rat to maintainnormal lear ning and memory;That NOS neurons appeared in granular cell layers of dentate gyr i and extracortex of pearform region may be a compensatory response.It is hypoth esized that both of them might play an important role in the subsequent cognitiv e recovery.
出处
《中国临床康复》
CSCD
2004年第13期2574-2575,F003,共3页
Chinese Journal of Clinical Rehabilitation
