跑台训练对急性高原低氧暴露大鼠海马髓鞘再生及认知功能的影响  

Effects of treadmill training on remyelination in hippocampus and cognitive function in rats exposed to acute plateau hypoxia

作　　者：张庆 刘媛[2] 罗浩东 苏虹 钟娟 杨策[2] 王海燕[2] 李森[2] 殷樱[1] 谭波涛[1] ZHANG Qing;LIU Yuan;LUO Haodong;SU Hong;ZHONG Juan;YANG Ce;WANG Haiyan;LI Sen;YIN Ying;TAN Botao(Department of Rehabilitation Medicine,the Second Affiliated Hospital of Chongqing Medical University,Chongqing,400010;State Key Laboratory of Trauma and Chemical Poisoning,Department of Special War Wound,Daping Hospital,Army Medical University(Third Military Medical University),Chongqing,400042,China)

机构地区：[1]重庆医科大学附属第二医院康复医学科,重庆400010 [2]陆军军医大学(第三军医大学)大坪医院特殊环境战伤防治研究室,创伤与化学中毒全国重点实验室,重庆400042

出　　处：《陆军军医大学学报》2024年第8期786-795,共10页Journal of Army Medical University

基　　金：创伤、烧伤与复合伤国家重点实验室开放课题(SKLKF20.2112);国家自然科学基金青年科学基金(82002377)。

摘　　要：目的探讨跑台训练对急性高原低氧暴露大鼠海马髓鞘结构及认知功能的影响。方法SPF级6~8周龄雌性SD大鼠30只(体质量200~220 g),6只用于损伤后髓鞘形态观察;其余24只随机分为(n=8):对照组、低压缺氧组和跑台训练组。实验组放入海拔6000 m的低压氧舱内,连续7 d。对照组动物放入密闭舱室内相同时间而不进行缺氧处理。跑台训练组于造模结束后第2天开始4周的跑台训练。训练结束后对各组大鼠进行旷场和Morris水迷宫实验检测观察大鼠认知功能变化;透射电镜(transmission electron microscopy,TEM)观察海马脱髓鞘改变;免疫荧光染色及Western blot检测海马CA1和CA3区少突胶质细胞转录因子2(oligodendrocyte transcription factor 2,Olig2)、髓鞘碱性蛋白(myelin basic protein,MBP)的表达情况。结果行为学检测结果显示:低压缺氧组进入旷场中心区域次数、总路程和路程比及Morris水迷宫穿越平台次数和目标区域路程较对照组减少(P<0.05),而跑台训练组较低压缺氧组有所增加(P<0.05)。免疫荧光染色显示:低压缺氧组海马CA1和CA3区单位面积内Olig2阳性细胞数量及MBP的平均荧光强度较对照组明显减少(P<0.05),而跑台训练组较低压缺氧组有所增加(P<0.05)。Western Blot结果显示:低压缺氧组海马Olig2和MBP蛋白表达水平较对照组显著降低(P<0.01),而跑台训练组较低压缺氧组有所增加(P<0.01)。结论跑台训练能够促进急性高原低氧暴露大鼠CA1和CA3区少突胶质谱系细胞数量和髓鞘相关蛋白的表达增加,并促进海马髓鞘结构修复,从而改善缺氧导致的焦虑样行为及记忆功能障碍。Objective To determine the effects of treadmill training on the structure of hippocampal myelin and cognitive function in rats exposed to acute plateau hypoxia.Methods With 30 SPF-grade female SD rats(aged 6-8 weeks,weighing 200-220 g),6 of them were used for observation of myelin structure after injury,and the remaining 24 rats were randomly divided into control group,hypobaric hypoxia group and treadmill training group(n=8).The rats in above experimental groups were placed in a low-pressure oxygen chamber at an altitude of 6000 m for 7 consecutive days,and the rats of the control group were placed in the confined chamber for the same period without hypoxia.Then,the rats of the treadmill training group received a 4-week treadmill training scheme since the day after hypoxia.Finally,all the rats were tested for cognitive function with open field test(OFT)and Morris water maze(MWM).Transmission electron microscopy(TEM)was used to observe the changes of demyelination in the hippocampus.The expression of oligodendrocyte transcription factor 2(Olig2)and myelin basic protein(MBP)in the hippocampal CA1 and CA3 regions was measured by immunofluorescence staining and Western blotting.Results Behavioral tests showed that the number into the central area,total distance,distance ratio in OFT and the number of platform crossings and distance to the target area in MWM were reduced in the hypobaric hypoxia group than the control group(P<0.05),while these indexes were increased in the treadmill training group than in the hypobaric hypoxia group(P<0.05).Immunofluorescence staining indicated that the number of Olig2 positive cells per unit area and the mean fluorescence intensity of MBP in the CA1 and CA3 regions were significantly lessen in the hypobaric hypoxia group than the control group(P<0.05),while these indicators were higher in the treadmill training group than the hypobaric hypoxia group(P<0.05).Western blotting displayed that the expression levels of Olig2 and MBP in the hippocampus were obviously lower in the hypobaric

关 键 词：低压缺氧 跑台训练 髓鞘再生 认知功能 

分 类 号：R322.81[医药卫生—人体解剖和组织胚胎学] R339.4[医药卫生—基础医学] R339.54