摘要
目的研究齿状回(dentate gyrus,DG)神经元在觉醒和睡眠状态下的放电活动差异及其在海马尖波涟漪波和θ振荡发生时的放电活动变化。方法选取6只3月龄SPF级雄性野生型C57BL/6小鼠,体质量22~25 g。以背侧海马场电位活动和头颈部三维加速度作为小鼠脑功能状态的评判指标,将脑功能状态分为觉醒、非快速眼动(non-rapid eye movement,NREM)睡眠和快速眼动(rapid eye movement,REM)睡眠。利用微电极阵列记录3种脑状态下小鼠DG神经元的峰电位发放活动,比较DG神经元在不同脑状态下的放电活动差异,并分析它们在海马尖波涟漪波和θ振荡过程中的放电活动特征。结果根据峰电位发放频率和峰电位谷-峰波宽特性将DG区神经元分为颗粒细胞、苔藓细胞和中间神经元3类。颗粒细胞(n=75)在NREM睡眠期的峰电位发放频率显著高于REM睡眠期和觉醒期(P<0.05);在NREM睡眠期海马尖波涟漪波振荡和REM睡眠期θ振荡发生时峰电位发放频率进一步增加(P<0.05)。苔藓细胞(n=27)在REM睡眠期的放电频率显著高于NREM睡眠期和觉醒期(P<0.05),但在NREM睡眠期与觉醒期的放电频率差异无统计学意义;苔藓细胞在NREM睡眠期间海马尖波涟漪波振荡和REM睡眠期θ振荡发生时峰电位发放频率显著增加(P<0.05)。中间神经元(n=9)在REM睡眠期间的放电频率显著高于NREM睡眠期(P<0.05),但与觉醒期的放电频率差异无统计学意义;中间神经元在NREM睡眠期海马尖波涟漪波振荡发生时,既可呈现发放增强模式(67%),也可呈现发放减弱模式(33%)。在REM睡眠期θ振荡发生时,中间神经元发放频率下降幅度最大(P<0.05)。结论DG区颗粒细胞和苔藓细胞在睡眠-觉醒周期中展现出不同的放电活动特征;颗粒细胞在NREM睡眠期间发放活动最强,而苔藓细胞则在REM睡眠期间发放活动最强。
ObjectiveTo investigate the difference of dentate gyrus(DG)neuronal activity between wakefulness and sleep state,and the characteristics of DG neuronal activity during hippocampal sharp wave ripple andθoscillations.MethodsSix 3monthdd male wildtype C57BL/6 mice(22~25 g)were employed.The oscillation state of local field potential in the dorsal hippocampus and threedimensional acceleration of the head and neck were used to determine the brain state which were classified into three types:wakefulness,nonrapid eye movement(NREM)sleep and rapid eye movement(REM)sleep.In vivo multielectrode arrays were utilized to record the firing activity of DG neurons under distinct states.ResultsThe DG neurons were divided into the granule cells,mossy cells and interneurons according to characteristics of spike rates and valleytopeak spike waveform width.The firing rates of granule cells(n=75)in NREM sleep were significantly higher than those in either REM sleep(P<0.05)or wakefulness(P<0.05).The granule cells exhibited further elevated spike activity during sharp wave ripples during NREM sleep andθoscillations during REM sleep(P<0.05).The firing rates of mossy cells(n=27)in REM sleep were significantly higher than in either NREM sleep(P<0.05)or wakefulness(P<0.05),but no statistical difference was observed in firing rates between NREM sleep and wakefulness.Likewise,the mossy cells exhibited increased spike activity during sharp wave ripples in NREM sleep andθoscillations in REM sleep(P<0.05).The firing rates of interneurons(n=9)during REM sleep were significantly higher than that in NREM sleep(P<0.05).However,there was no significant difference in spike activities of interneurons between NREM sleep and wakefulness.67%of the DG interneurons increased their spike activities,whereas the remaining interneurons(33%)decreased their spike activities during sharp wave ripples.The spike activity of interneurons had greatest decline among 3 types of DG neurons(P<0.05).ConclusionThe granule cells and mossy cells in the DG area are significa
作者
张海波
杨叶
陈辉
王斌
王博
胡波
ZHANG Haibo;YANG Ye;CHEN Hui;WANG Bin;WANG Bo;HU Bo(Department of Physiology,College of Basic Medical Sciences,Army Medical University(Third Military Medical University),Chongqing,400038,China;Department of Histoembryology,College of Basic Medical Sciences,Army Medical University(Third Military Medical University),Chongqing,400038,China)
出处
《陆军军医大学学报》
CAS
CSCD
北大核心
2023年第24期2495-2502,共8页
Journal of Army Medical University
基金
国家自然科学基金面上项目(32170982)。
关键词
齿状回
海马
觉醒
睡眠
尖波涟漪波
θ振荡
dentate gyrus
hippocampus
wakefulness
sleep
sharp wave ripple
θoscillation
