摘要
目的探讨二氢杨梅素(dihydromyricetin,DHM)对间歇低氧大鼠认知功能及海马齿状回微管相关蛋白2(MAP-2)表达的影响。方法54只Wistar大鼠随机分为正常组、间歇低氧组及DHM组(n=18),在实验6周、8周、12周3个时间点每组各取6只大鼠,应用Morris水迷宫检测大鼠的记忆功能;免疫组织化学法观察海马齿状回MAP-2表达;透射电镜观察海马齿状回突触的超微结构。结果在相同时间点,与正常组比较,间歇低氧组及DHM组大鼠逃避潜伏期明显延长,跨越目标象限时间明显缩短,MAP-2表达明显降低(P<0.05);与间歇低氧组比较,DHM组大鼠实验6周、8周、12周逃避潜伏期明显缩短[(37.57±3.55)s vs(67.88±3.17)s,(49.05±3.30)s vs(75.13±2.85)s,(57.90±3.42)s vs(84.22±3.59)s],跨越目标象限时间明显延长[(39.38±2.69)s vs(20.96±2.25)s,(30.60±3.02)s vs(17.32±2.91)s,(24.59±2.59)s vs(11.26±3.11)s],MAP-2表达明显升高(47.26±4.18 vs 33.89±2.64,39.08±4.59 vs 24.64±2.43,27.24±3.51 vs 14.15±4.01),差异有统计学意义(P<0.05)。电镜下正常组大鼠海马齿状回突触小泡丰富,突触及细胞器结构正常;与正常组比较,间歇低氧组突触小泡减少,结构不清,细胞器损伤;与间歇低氧组比较,DHM组大鼠海马齿状回突触损伤减轻。结论DHM可改善间歇低氧大鼠认知功能,这可能与增加海马齿状回MAP-2表达改善突触可塑性有关。
Objective To study the effect of dihydromyricetin(DHM) on cognitive function and microtubule-associated protein 2(MAP-2) expression in hippocampal dentate gyrus in intermittent hypoxia rats.Methods Fifty-four Wistar rats were randomly divided into normal group, intermittent hypoxia group and DHM group(18 in each group).Six rats were selected from each group at weeks 6,8 and 12.Their memory was tested in Morris water maze experiment.The expression of MAP-2 in hippocampal dentate gyrus was detected with immunohistochemical method.The ultrastructure of hippocampal dentate gyrus synapse was observed by transmission electron microscopy.Results The escape latent period was significantly longer while the target quadrant crossing time was significantly shorter and the MAP-2 expression level was significantly lower in intermittent hypoxia group and DHM group than in normal group at the same time point(P<0.05).The escape latent period was significantly shorter while the target quadrant crossing time was significantly longer in DHM group than in intermittent hypoxia group at weeks 6,8 and 12(37.57±3.55 s vs 67.88±3.17 s, 49.05±3.30 s vs 75.13±2.85 s, 57.90±3.42 s vs 84.22±3.59 s;39.38±2.69 s vs 20.96±2.25 s, 30.60±3.02 s vs 17.32±2.91 s, 24.59±2.59 s vs 11.26±3.11 s;47.26±4.18 vs 33.89±2.64,39.08±4.59 vs 24.64±2.43,27.24±3.51 vs 14.15±4.01;P<0.05).Transmission electron microscopy showed abundant synaptic vesicles and normal synaptic and organelle structure in hippocampal dentate gyrus in normal group.The number of synaptic vesicles was smaller, the structure of synaptic vesicles was unclearer and the damage of organelle was severer in intermittent hypoxia group than in normal group.The damage of synapse was milder in DHM group than in intermittent hypoxia group.Conclusion DHM can improve the cognitive function in intermittent hypoxia rats, which is possibly related with the synaptic plasticity improved by the elevated MAP-2 protein expression in hippocampal dentate gyrus.
作者
王玲
杨馥宇
Wang Ling;Yang Fuyu(Department of Respiratory Diseases,Affiliated Hospital of North China University of Science and Technology,Tangshan 063000,Hebei Province,China)
出处
《中华老年心脑血管病杂志》
北大核心
2022年第4期422-425,共4页
Chinese Journal of Geriatric Heart,Brain and Vessel Diseases
基金
河北省医学科学研究课题(20201244,20210742)。
关键词
认知
睡眠呼吸暂停
阻塞性
齿状回
微管相关蛋白质类
低氧
细胞器
突触
cognition
sleep apnea
obstructive
dentate gyrus
microtubule-associated proteins
hypoxia
organelles
synapses
