睡前興奮影響入睡是經(jīng)驗之談,。而最近日本筑波大學(xué)研究人員通過動物實驗從科學(xué)角度予以證實:睡前主動保持清醒狀態(tài),,一旦想睡覺,入睡會比較困難,。
研究人員將實驗鼠分為兩組,,在實驗鼠通常睡覺的時間段進行實驗。研究人員通過觸碰其中一組實驗鼠的身體干擾它們的睡眠,,讓實驗鼠連續(xù)6小時沒法睡覺,,“迫不得已保持清醒狀態(tài)”;而對另一組實驗鼠,,研究人員每小時更換一次鼠窩,,讓實驗鼠不斷探索新環(huán)境,勾起它們的好奇心和警戒心,,使實驗鼠連續(xù)6小時“自發(fā)處于清醒狀態(tài)”,。
然后,實驗小組測定了實驗鼠進入睡眠狀態(tài)的時間,,發(fā)現(xiàn)睡眠受干擾的實驗鼠平均兩三分鐘就進入了夢鄉(xiāng),但是老被變換環(huán)境的實驗鼠,,進入睡眠的時間平均達到15分鐘,。但是研究人員調(diào)查實驗鼠睡眠時的腦電波,發(fā)現(xiàn)兩組實驗鼠大腦需求的睡眠量幾乎相同,。
筑波大學(xué)教授柳澤正史指出,,調(diào)查睡前活動對睡眠的影響,將有助于治療失眠,,促進失眠癥患者改善生活習(xí)慣,。
6月18日一期的美國《國家科學(xué)院學(xué)報》網(wǎng)絡(luò)版上公布了上述成果。(生物谷Bioon.com)
生物谷推薦英文摘要:
PNAS doi:10.1073/iti2513110
Behavioral and biochemical dissociation of arousal and homeostatic sleep need influenced by prior wakeful experience in mice
Ayako Suzukia,b,c, Christopher M. Sintond,1, Robert W. Greeneb,e,f,2, and Masashi Yanagisawaa,c,f
Sleep is regulated by homeostatic mechanisms, and the low-frequency power in the electroencephalogram (delta power) during non-rapid eye movement sleep reflects homeostatic sleep need. Additionally, sleep is limited by circadian and environmentally influenced arousal. Little is known, however, about the underlying neural substrates for sleep homeostasis and arousal and about the potential link between them. Here, we subjected C57BL/6 mice to 6 h of sleep deprivation using two different methods: gentle handling and continual cage change. Both groups were deprived of sleep to a similar extent (>99%), and, as expected, the delta power increase during recovery sleep was quantitatively similar in both groups. However, in a multiple sleep latency test, the cage change group showed significantly longer sleep latencies than the gentle handling group, indicating that the cage change group had a higher level of arousal despite the similar sleep loss. To investigate the possible biochemical correlates of these behavioral changes, we screened for arousal-related and sleep need-related phosphoprotein markers from the diencephalon. We found that the abundance of highly phosphorylated forms of dynamin 1, a presynaptic neuronal protein, was associated with sleep latency in the multiple sleep latency test. In contrast, the abundance of highly phosphorylated forms of N-myc downstream regulated gene 2, a glial protein, was increased in parallel with delta power. The changes of these protein species disappeared after 2 h of recovery sleep. These results suggest that homeostatic sleep need and arousal can be dissociated behaviorally and biochemically and that phosphorylated N-myc downstream regulated gene 2 and dynamin 1 may serve as markers of homeostatic sleep need and arousal, respectively.