剥夺小鼠睡眠后促觉醒中枢TMN内小胶质细胞在睡眠-觉醒中的变化

The changes of microglial cells in the tuberomammillary nucleus after the sleep deprivation

目的探讨剥夺小鼠睡眠后促觉醒中枢结节乳头体核(TMN)内小胶质细胞的变化规律。方法将C57BL/6小鼠随机分为生理盐水自然睡眠组(NS-TODS)、腹腔注射米诺环素自然睡眠组(mino-TODS)、睡眠剥夺生理盐水组(NSSD)和腹腔注射米诺环素后睡眠剥夺组(mino-SD)。采用脑立体定位埋放电极、多导睡眠描计技术和免疫荧光法观察4组小鼠的睡眠和觉醒时间以及小胶质细胞形态的变化。结果(1)NS-TODS组和mino-TODS组小鼠在觉醒(W)、快速眼动(REM)睡眠以及非快速眼动(NREM)睡眠时间呈昼夜节律变化,两者之间差异无统计学意义;(2)与NS-TODS相比,NS-SD组可见明显的睡眠增加,主要表现在非快速眼动(NREM)睡眠总量增加(P<0.05),觉醒时间减少(P<0.05);(3)与NS-SD组相比,mino-SD组在ZT 5~6时间段内,其觉醒总量增多(P<0.05),睡眠总量减少(P<0.05),但在ZT 6~11时段内,无显著性变化;(4)与NS-TODS相比,NS-SD组睡眠剥夺5 h后,TMN区的小胶质细胞直径明显增大(P<0.01),其荧光强度增强(P<0.05);而mino-SD组睡眠剥夺5 h后,小胶质细胞体积有变小的趋势,但差异无统计学意义。结论 TMN内的小胶质细胞可能参与睡眠-觉醒稳态的调节。

Objective To investigate the changes of microglial cells in the tuberomammillary nucleus（ TMN） after sleep deprivation. Methods C57 BL/6 mice were randomly divided into the normal saline with time of day sleep group（ NS-TODS）,the intraperitoneal injection of minocycline with time of day sleep group（ mino-TODS）,the normal saline with sleep-deprived group（ NS-SD）,and the intraperitoneal injection of minocycline with sleep-deprivation group（ mino-SD）. To observe the changes of sleep time,wakefulness time and microglia morphology in four groups of mice by using the brain stereotactic embedding electrode,multiple-guided sleep mapping technique and immunofluorescence method. Results（1） Mice in NS-TODS group and mino-TODS group had a regular circadian rhythm and there was no statistically significant difference between them during wakefulness（ W）,rapid eye movement（ REM） sleep,and non-rapid eye movement（ NREM） sleep time.（2） Compared with that in NS-TODS group,NREM sleep was increased significantly in NS-SD group of sleep time（ P〈0.05）. And the wake time in NS-SD group reduced（ P〈0.05）.（3） Compared with that in NS-SD group,during the ZT 5 ~ 6 time,the total time of wake of mino-TODS increased（ P〈0.05）,and the total time of sleep reduced（ P〈0.05）,but during the period of ZT 6 ~ 11 time,there was no obvious changes.（4） Compared with that in NS-TODS group,after five hours of sleep deprivation in the NS-SD group,the diameter of microglia in the TMN area increased significantly（ P〈0. 01）,and the fluorescence intensity increased（ P〈0.05）,while there was a tendency to decrease the volume of microglia after five hours of sleep deprivation in the mino-SD group,but there was no statistical difference. Conclusion Microglia cells of TMN may be involved in the regulation of sleep-wake homeostasis.