寒冷刺激对部分睡眠剥夺小鼠血细胞参数的影响

目的：探讨寒冷刺激,部分睡眠剥夺,以及部分睡眠剥夺的基础上再给予寒冷刺激等处理对小鼠血细胞参数的影响。方法：昆明小鼠24只,随机均分为4组（n=6）：对照组、寒冷组、不完全睡眠剥夺组和不完全睡眠剥夺加寒冷组。寒冷组每天给予（10±2）℃的低温处理4h,不完全睡眠剥夺组每天18：00至次日9：00剥夺睡眠,不完全睡眠剥夺加寒冷组在每天睡眠剥夺的基础上再给予4h寒冷刺激。连续处理4d后采血检测血常规和血沉率。结果：与对照组相比,寒冷刺激可使小鼠血液中淋巴细胞含量（P〈0．05）以及百分比（P〈0．01）显著增加;部分睡眠剥夺可使小鼠血液白细胞和淋巴细胞含量（P〈0．05）及百分比（P〈0．01）明显降低。不完全睡眠剥夺加寒冷刺激处理后与其它三组相比小鼠血液白细胞和淋巴细胞含量显著降低（P〈0．01）,而血沉率则显著升高（P〈0．01）。结论：部分睡眠剥夺会抑制机体免疫能力,在部分剥夺睡眠的基础上再给予寒冷刺激则将进一步抑制机体免疫能力并使血沉率加快,降低机体对外界环境变化的适应能力。     

慢性睡眠剥夺对颞下颌关节微结构的影响

目的:研究慢性睡眠障碍对大鼠颞下颌关节微结构的影响。方法:采用改良多平台法(MMPM)建立睡眠剥夺模型,将90只Wistar大鼠随机分为3组(n=30),分别为小平台组、网格组和对照组。小平台组和网格组大鼠接受每天18 h的睡眠剥夺和6 h间歇期(10:00—16:00),间歇期大鼠正常笼养。实验第7、14和21天时分别行动物行为学观察、旷场试验和动物血浆检测,并通过HE染色和扫描电镜观察颞下颌关节微结构的变化。结果:与对照组和网格组相比,小平台组大鼠血清促肾上腺激素(ACTH)和皮质醇(CORT)水平均增高(P<0.05),髁突软骨HE染色显示软骨细胞层次及厚度改变;扫描电镜结果显示关节盘表面纤维排列松散。结论:慢性睡眠障碍可能导致颞下颌关节微结构发生病理性改变。     

完全睡眠剥夺对大脑注意网络冲突效应和脑电样本熵的影响*

目的: 本研究分析睡眠剥夺对个体选择性注意网络冲突效应和脑电样本熵的影响,探讨睡眠剥夺对大脑注意网络的影响。方法: 25名健康受试者参与36 h完全睡眠剥夺试验。试验于当天9:00开始,于次日21:00结束,试验采用自身前后对照设计。受试者在睡眠剥夺前后分别完成注意网络任务,同步采集受试者的脑电图。用脑电样本熵算法分析脑电图的delta、theta、alpha、beta和gamma频率段的脑电复杂度并对比各频段脑电样本熵在睡眠剥夺前、后的变化。结果: 同睡眠剥夺前比较,睡眠剥夺后与受试者的注意网络冲突效应密切相关的反应时显著下降(P＜0.01),正确率显著增加(P＜0.01)。脑电样本熵分析发现在beta频率段,与注意网络冲突控制相关的脑电样本熵值在睡眠剥夺后明显增大(P＜0.01)。其余脑电频率段脑电样本熵未发现显著差异。结论: 表明完全睡眠剥夺后大脑的注意网络冲突效应降低,表明睡眠剥夺后执行冲突控制能力的下降。     

MMP-1、MMP-3 和MMP-13在慢性睡眠剥夺所致颞下颌关节损伤中的变化

目的：观察MMP-1、MMP-3 和MMP-13 在慢性睡眠剥夺所致颞下颌关节损伤中表达的变化,探讨慢性睡眠剥夺所致颞下颌 关节损伤的可能机制。方法：采用改良多平台(MMPM)建立大鼠慢性睡眠剥夺模型,将90 只成年雄性Wastar 大鼠随机分为小平 台组、网格组和对照组。小平台组和网格组大鼠接受每天18 h的睡眠剥夺和6 h间歇期(10:00-16:00),间歇期大鼠正常笼养。实验 第7、14 和21 d时分别观察动物的行为学观察、检测动物血浆皮质醇(CORT)和促肾上腺皮质激素(ACTH)水平检测,通过免疫印 迹法和实时定量聚合酶链反应(PRC)检测颞下颌关节软骨中MMP-1、MMP-3 和MMP-13 的蛋白和mRNA表达,并通过HE 染色 法观察颞下颌关节结构的变化。结果：与对照组和网格组大鼠相比,小平台组大鼠第14 d和21 d 时髁突软骨中间部位表面纤维 在出现明显的炎症、松解及脱落现象;第21天时的血浆ACTH 和CORT 水平均显著高于网格组和对照组,差异有统计学意义 (P<0.05);第7、14、21 d时关节软骨MMP-1 和MMP-13 蛋白和mRNA 的表达水平均显著上调(P<0.05)。结论：慢性睡眠剥夺所致 的颞下颌关节损伤可能与关节软骨中MMP-1、MMP-3 和MMP-13 的表达上调有关。     

补充支链氨基酸对睡眠剥夺大鼠行为和血清游离脂肪酸水平的影响

探讨补充支链氨基酸 (branched -chainaminoacids ,BCAA)对睡眠剥夺 (sleepdeprivation ,SD)大鼠的行为和血清游离脂肪酸 (freefattyacids,FFA)水平的影响。采用小站台水环境 (flower -pot)睡眠剥夺模型对大鼠进行睡眠剥夺。成年、雄性Sprague-Dawley大鼠 5 6只 ,按体重随机分为C(对照组、自由睡眠 )、2 4hSD(剥夺睡眠 2 4h)、2 4hSDB(睡眠剥夺 2 4h ,进食添加BCAA的饲料 )、4 8hSD、4 8hSDB、72hSD、72hSDB组 ,每组 8只。睡眠剥夺结束后 ,采用旷场实验 (openfieldtest,OPT)评价大鼠的精神行为。结果各睡眠剥夺组大鼠的OFT得分均显著高于对照组 (P <0 .0 5 ) ;其中以 4 8hSD组最高 ,72hSD组的OFT得分又显著低于 72hSDB组 (P <0 .0 5 )。睡眠剥夺各组大鼠血清FFA水平均显著高于非剥夺组 ,72hSDB组显著高于 72hSD组 (P <0 .0 5 )。结论为补充支链氨基酸可以改善睡眠剥夺大鼠的旷场实验行为 ,降低睡眠剥夺大鼠血清FFA水平。     

36 h完全睡眠剥夺对客体工作记忆相关电位的影响*

目的:采用事件相关电位(ERP)技术探讨36 h完全睡眠剥夺对客体工作记忆的影响。方法:本研究采用自身前后对照设计,16名睡眠质量良好的健康大学生(平均年龄为23岁,年龄范围21～28岁)分别在清醒状态下及36 h完全睡眠剥夺后接受2-back客体工作记忆任务,同时采集脑电数据。选用重复测量方差分析的方法比较睡眠剥夺前后与客体工作记忆有关的P2、N2、P3成分的波幅和潜伏期的差异。结果:在36 h完全睡眠剥夺后,与客体工作记忆加工相关的N2波的潜伏期显著延长(P＜0.05),波幅减少但未见统计学差异(P＞0.05); P2波潜伏期显著延长(P＜0.05),波幅未见明显变化(P＞0.05)。P3波波幅、潜伏期未见统计学差异(P＞0.05)。结论:36 h的完全睡眠剥夺影响了客体工作记忆相关电位,损害了个体的客体工作记忆加工能力。     

不同时间睡眠剥夺对大鼠运动能力及谷氨酰胺的影响

目的：探索睡眠剥夺对大鼠运动能力及谷氨酰胺含量变化的影响,为睡眠剥夺后的运动训练等提供一定的实验依据。方法：将30只雄性SD大鼠按体重随机分安静对照组、0h睡眠剥夺力竭运动组（SDE）、24h SDE、48h SDE和72h SDE组（n=6）,采用轻柔刺激法建立睡眠剥夺模型和依据Bedford建立的大鼠运动模型。结果：24h SDE睡眠剥夺组与0h SDE组比较。大鼠后蹬跑时间明显长（P〈0．05）,48h SDE睡眠剥夺组和72h SDE睡眠剥夺与0h SDE睡眠剥夺组比较,后蹬跑时间显著性减少（P〈0．01）;24h SDE睡眠剥夺组与c组比较大鼠胸腺谷氨酰胺含量显著升高（P〈0．05）,48h SDE睡眠剥夺组和72h SDE睡眠剥夺组与C组比较大鼠胸腺谷氨酰胺含量降低（P〈0．01）;睡眠剥夺组与C组比较,血清谷氨酰胺含量的变化均具有高度显著性差异（P〈0．01）,睡眠剥夺24h后血清谷氨酰胺含量显著增多,却在睡眠剥夺48h、72h后血清谷氨酰胺含量明显下降。结论：①睡眠剥夺24h能提高大鼠运动能力,睡眠剥夺48h甚至是72h后大鼠运动能力开始降低。②睡眠剥夺24h后大鼠胸腺谷氨酰胺含量和血清谷氨酰胺含量升高,而睡眠剥夺48h后大鼠胸腺和血清的谷氨酰胺含量下降明显,睡眠剥夺72h后胸腺和血清谷氨酰胺含量显著性降低。     

纳米氧化铈对48h睡眠剥夺小鼠生精能力的影响

为了研究纳米氧化铈(cerium oxide nanoparticles, CeO2NPs)对48 h睡眠剥夺小鼠生精能力的影响,并探讨其作用机制。将36只6周龄雄性健康清洁级ICR小鼠分为6组:空白对照组、溶剂对照组、睡眠剥夺对照组、CeO2NPs低、中、高剂量组。CeO2NPs低、中、高剂量组分别以4 mg/kg、8 mg/kg和16 mg/kg灌胃1 m L的纳米氧化铈溶液,溶剂对照组和睡眠剥夺对照组灌胃等量溶剂,空白对照组灌胃等量蒸馏水,连续30 d。第31天,采用单平台水环境法进行48 h睡眠剥夺。继之,测定小鼠每日精子生成量、睾丸组织内标志酶(G6PDH,LDH和ACP)及抗氧化指标(CAT, MDA和T-AOC)。与溶剂对照组比较,48 h睡眠剥夺使小鼠睾丸每日精子生成量降低,睾丸标志酶G6PDH、ACP和LDH活力下调,睾丸组织CAT活力和T-AOC水平降低,小鼠睾丸MDA含量升高。与睡眠剥夺对照组比较,CeO2NPs低、中、高剂量组均改善了48 h睡眠剥夺小鼠的每日精子生成量,其中中剂量组的改善更为明显,且在调节睡眠剥夺小鼠睾丸标志酶G6DPH、LDH和ACP活力、提高睾丸组织内CAT活力、T-AOC水平及降低MDA含量方面最为显著。纳米氧化铈可以改善睡眠剥夺雄性小鼠的生精能力,这可能与提高了睾丸组织的抗氧化能力,从而改善了氧化应激损伤并调节了能量消耗代谢有关。     

负性情绪对不同视野条件下工作记忆的影响

目的:研究结合延迟样本匹配任务和分视野范式,探讨负性情绪对言语和空间工作记忆的影响。方法:32名大学本科生参加实验,在中性和负性情绪图片呈现阶段,所有被试完成言语和空间工作记忆任务各160个trial。结果:言语工作记忆任务在右视野呈现时正确率较高,反应时较短,而空间工作记忆任务则在左视野呈现时表现出相似的反应优势;负性情绪状态下的工作记忆表现均优于中性情绪状态。结论:言语及空间工作记忆分别具有左、右半球的加工优势,且负性情绪对工作记忆具有促进作用。     

慢性睡眠剥夺加重APP/PS1/tau小鼠学习记忆能力和病理损伤

睡眠在认知功能和情绪的调节过程中发挥重要作用。近年研究显示,睡眠障碍是阿尔茨海默病(Alzheimer’s disease,AD)重要的危险因素之一,但慢性睡眠剥夺对于AD模型小鼠认知功能的影响及其机制尚不明确。本研究采用改良多平台法对8月龄雄性APP/PS1/tau三转基因AD模型(3xTg-AD)小鼠和野生型(wild type, WT)小鼠(每组8只)进行连续21天、每天20 h的睡眠剥夺。睡眠剥夺结束后,采用旷场、高架十字迷宫、糖水偏好、物体识别、Y迷宫和条件恐惧记忆实验等多种行为学手段观察慢性睡眠剥夺对3xTg-AD小鼠的焦虑和抑郁样行为以及多种认知功能的影响,并通过免疫组织化学染色观察小鼠海马区β淀粉样蛋白(amyloidβprotein, Aβ)斑块沉积、神经原纤维缠结和小胶质细胞的活化程度。结果显示:(1)慢性睡眠剥夺未影响3xTg-AD小鼠的焦虑(P=0.539)和抑郁样行为(P=0.874);(2)慢性睡眠剥夺加重了3xTg-AD小鼠的识别记忆(P 0.001)、工作记忆(P=0.002)和条件恐惧记忆能力(P=0.039)损伤;(3)慢性睡眠剥夺增加了3xTg-AD小鼠海马区Aβ斑块的沉积(P 0.001)和小胶质细胞的过度活化(P 0.001),但并未导致tau蛋白异常磷酸化和神经原纤维缠结出现。以上结果表明,慢性睡眠剥夺加重了3xTg-AD小鼠的识别记忆、工作记忆和条件恐惧记忆能力损伤,且其损伤作用与3xTg-AD小鼠海马区Aβ斑块沉积增加和小胶质细胞过度活化密切相关。     

Modafinil improves performance in the multiple T-Maze and modifies GluR1, GluR2, D2 and NR1 receptor complex levels in the C57BL/6J mouse

Modafinil has been shown to modify behavioural and cognitive functions and to effect several brain receptors. Effects, however, were not observed at the receptor protein complex level and it was therefore the aim of the study to train mice in the multiple T-Maze (MTM) as a paradigm for spatial memory and to determine paralleling brain receptor complex levels. Sixty C57BL/6J mice were used in the study and divided into four groups (trained drug injected; trained vehicle injected; yoked drug injected; yoked vehicle injected). Animals obtained training for 4?days and were killed 6?h following the last training session on day 4. Hippocampi were dissected from the brain, membrane fractions were prepared by ultracentrifugation and were run on blue-native gels and immunoblotted with antibodies against major brain receptors. Modafinil treatment led to decreased latency and increased average speed, but not to changes in pathlength and number of correct decisions in the MTM. Drug effects were modifying receptor complexes of GluR1, GluR2, D2 and NR1. Training effects on receptor complex levels were observed for GluR3, D1 and nicotinic acetylcholine receptor alpha 7 (Nic7). GluR1 levels were correlating with GluR2 and D1 levels were correlating with D2 and NR1. Involvement of the glutamatergic, NMDA, dopaminergic and nicotinergic system in modafinil and memory training were herein described for the first time. A brain receptor complex pattern was revealed showing the concerted action following modafinil treatment.     

Efficacy of Modafinil on Fatigue and Excessive Daytime Sleepiness Associated with Neurological Disorders: A Systematic Review and Meta-Analysis

Background

Modafinil is a novel wake-promoting agent approved by the FDA ameliorating excessive daytime sleepiness (EDS) in three disorders: narcolepsy, shift work sleep disorder and obstructive sleep apnea. Existing trials of modafinil for fatigue and EDS associated with neurological disorders provided inconsistent results. This meta-analysis was aimed to assess drug safety and effects of modafinil on fatigue and EDS associated with neurological disorders.

Methods

A comprehensive literature review was conducted in order to identify published studies assessing the effects of modafinil on fatigue and EDS associated with neurological disorders. Primary outcomes included fatigue and EDS. Secondary outcomes included depression and adverse effects.

Findings

Ten randomized controlled trials were identified including 4 studies of Parkinson’s disease (PD), 3 of multiple sclerosis (MS), 2 of traumatic brain injury (TBI) and 1 of post-polio syndrome (PPS). A total of 535 patients were enrolled. Our results suggested a therapeutic effect of modafinil on fatigue in TBI (MD -0.82 95% CI -1.54 - -0.11 p=0.02, I²=0%), while a beneficial effect of modafinil on fatigue was not confirmed in the pooled studies of PD or MS. Treatment results demonstrated a clear beneficial effect of modafinil on EDS in patients with PD (MD -2.45 95% CI -4.00 - -0.91 p=0.002 I²=14%), but not with MS and TBI. No difference was seen between modafinil and placebo treatments in patients with PPS. Modafinil seemed to have no therapeutic effect on depression. Adverse events were similar between modafinil and placebo groups except that more patients were found with insomnia and nausea in modafinil group.

Conclusions

Existing trials of modafinil for fatigue and EDS associated with PD, MS, TBI and PPS provided inconsistent results. The majority of the studies had small sample sizes. Modafinil is not yet sufficient to be recommended for these medical conditions until solid data are available.     

The features of sleep homeostasis in pregnant rats

To investigate the effects of short-term sleep deprivation on the sleep pattern during pregnancy, cortical and hippocampal EEG and locomotor activity were recorded within 24-hours in a "disk-over-water" paradigm in 18 Wistar rats. Rats were adapted to experimental situation and were able to move across the rotating disk without falling in water. Then a polysomnogram was recorded for 3 sequential days in the control group 1 (n = 12) without disk rotation. On the next day non-pregnant rats (experimental group 1, n = 6) were subjected to the sleep deprivation procedure with a pre-set program of disk rotation from 11:00 to 14:00 during 3 sequential days. Other 6 rats (experimental group 2) were subjected to sleep deprivation on the 5-7th day of pregnancy. EEG and locomotor activity were also constantly recorded during the sleep deprivation procedure. In control group 2 (n = 6, without sleep deprivation), a polysomnogram was recorded on the 5-7th day of pregnancy. As compared to non-pregnant rats, sleep intensity of pregnant rats increased during the first hours after the deprivation, and a considerable rebound of REM sleep took place. Sleep pattern during the off-light 12 hours remained unchanged. The results suggest that homeostatic compensation of sleep deprivation effects in rats on the first week of pregnancy is more efficient than in control non-pregnant animals.     

The Effect of One Night's Sleep Deprivation on Temperature,Mood, and Physical Performance in Subjects with Different Amounts of Habitual Physical Activity

Eleven healthy males were studied twice. On one occasion (control, C), they slept (night 1) and then underwent a battery of tests at 4h intervals from 06: 00 day 1 to 02: 00 day 2; then, after a normal sleep (night 2), they were tested from 10: 00 to 22: 00 on day 2. On the second occasion (sleep deprivation, SD), the subjects remained awake during night 1. Each battery of tests consisted of measurements of tympanic membrane temperature, profile of mood states (POMS), muscle strength, self-chosen work rate (SCWR), perceived exertion, and heart rate (HR) while exercising on a stationary cycle ergometer. Subjects also kept a diary of their activities during the two days and answered a questionnaire about their habitual physical activity. Results showed a significant negative effect of sleep deprivation on most mood states on day 1, but no effect on the other variables. By day 2, mood had tended to recover, though muscle strength tended to be worse in both control and sleep-deprivation experiments. There was also a more general tendency for negative effects to be present at the end of day 1 (02: 00) or at the beginning of day 2 (10: 00). There was limited support for the view that subjects who were habitually more active showed less negative effects after sleep deprivation and responded less adversely to the poor sleep achieved on the university premises (night 2). These results stress the considerable interindividual variation in the responses to sleep loss and, therefore, the difficulty associated with giving general advice to individuals about work or training capability after sleep loss.     

Gambling when sleep deprived: don't bet on stimulants

Recent evidence suggests that sleep deprivation leads to suboptimal decision-making on the Iowa Gambling Task (IGT), a pattern that appears to be unaffected by moderate doses of caffeine. It is not known whether impaired decision-making could be reversed by higher doses of caffeine or by other stimulant countermeasures, such as dextroamphetamine or modafinil. Fifty-four diurnally active healthy subjects completed alternate versions of the IGT at rested baseline, at 23 and 46?h awake, and following a night of recovery sleep. After 44?h awake, participants received a double-blind dose of caffeine (600?mg), dextroamphetamine (20?mg), modafinil (400?mg), or placebo. At baseline, participants showed a normal pattern of advantageous performance, whereas both sleep-deprived sessions were associated with suboptimal decision-making on the IGT. Following stimulant administration on the second night of sleep deprivation, groups receiving caffeine, dextroamphetamine, or modafinil showed significant reduction in subjective sleepiness and improvement in psychomotor vigilance, but decision-making on the IGT remained impaired for all stimulants and did not differ from placebo. Decision-making returned to normal following recovery sleep. These findings are consistent with prior research showing that sleep deprivation leads to suboptimal decision-making on some types of tasks, particularly those that rely heavily on emotion processing regions of the brain, such as the ventromedial prefrontal cortex. Moreover, the deficits in decision-making were not reversed by commonly used stimulant countermeasures, despite restoration of psychomotor vigilance and alertness. These three stimulants may restore some, but not all, aspects of cognitive functioning during sleep deprivation.     

Caffeine reversal of sleep deprivation effects on alertness,mood and repeated sprint performances in physical education students

The aim of this study was to evaluate the effects of caffeine ingestion and partial sleep deprivation on mood and cognitive and physical performances. In randomised order, 12 healthy male physical education students completed four test sessions at 18:00 h after placebo or 5 mg/kg of caffeine ingestion during a baseline night (RN) (bed time: from 22:00 to 07:00 h), or during a night of partial (four hrs) sleep deprivation (PSD). During each test session, participants performed a reaction time test, a vigilance test, the 10 s Wingate cycling test during (measuring peak power (PP) and anaerobic capacity), and the 5 m multiple shuttle test (measuring peak distance (PD), total distance (TD), and fatigue index (FI)). Compared to RN, simple reaction time, vigilance, PP, PD, TD, and FI were altered by PSD the following day after placebo ingestion with increased reaction time and FI and reduced PP, PD, TD, and vigilance (p < 0.001). Moreover, during PSD condition, PP, PD, and TD were significantly higher after caffeine ingestion in comparison with placebo ingestion (p < 0.05). However, both simple reaction times and vigilance were significantly lower after caffeine ingestion in comparison with placebo during PSD (p < 0.05). Caffeine is an effective strategy to maintain physical and cognitive performances the day after PSD.     

The effects of two types of sleep deprivation on visual working memory capacity and filtering efficiency

Sleep deprivation has adverse consequences for a variety of cognitive functions. The exact effects of sleep deprivation, though, are dependent upon the cognitive process examined. Within working memory, for example, some component processes are more vulnerable to sleep deprivation than others. Additionally, the differential impacts on cognition of different types of sleep deprivation have not been well studied. The aim of this study was to examine the effects of one night of total sleep deprivation and 4 nights of partial sleep deprivation (4 hours in bed/night) on two components of visual working memory: capacity and filtering efficiency. Forty-four healthy young adults were randomly assigned to one of the two sleep deprivation conditions. All participants were studied: 1) in a well-rested condition (following 6 nights of 9 hours in bed/night); and 2) following sleep deprivation, in a counter-balanced order. Visual working memory testing consisted of two related tasks. The first measured visual working memory capacity and the second measured the ability to ignore distractor stimuli in a visual scene (filtering efficiency). Results showed neither type of sleep deprivation reduced visual working memory capacity. Partial sleep deprivation also generally did not change filtering efficiency. Total sleep deprivation, on the other hand, did impair performance in the filtering task. These results suggest components of visual working memory are differentially vulnerable to the effects of sleep deprivation, and different types of sleep deprivation impact visual working memory to different degrees. Such findings have implications for operational settings where individuals may need to perform with inadequate sleep and whose jobs involve receiving an array of visual information and discriminating the relevant from the irrelevant prior to making decisions or taking actions (e.g., baggage screeners, air traffic controllers, military personnel, health care providers).