根據(jù)6月30日的Journal of Neuroscience雜志上的一項最新研究,，在睡眠的初始階段，大腦一些區(qū)域中的能量水平顯著降低,，而這些區(qū)域在清醒狀態(tài)下是表現(xiàn)活躍的,。研究表明大腦在睡眠的時候經(jīng)歷著細胞能量的補充過程，該過程對清醒狀態(tài)下大腦執(zhí)行正常的功能來說是必需的,。
晚間良好的休息能夠使我們恢復(fù)精力,，但是在睡眠過程中實際發(fā)生的生物學(xué)過程卻很難捉摸?？茖W(xué)家認為大腦的能量水平是夜間恢復(fù)的關(guān)鍵,。文章作者Basheer教授表示，他們的這項研究將解釋一個重要的生物學(xué)問題,，即睡眠的功能,。在某種程度上他們也有點驚訝,，因為最近這些年還沒有科研人員使用最敏感的測量方法進行大腦能量研究。
在這項研究中,，研究人員測量了大鼠中三磷酸腺苷（ATP）的水平，結(jié)果發(fā)現(xiàn)當老鼠處在非快速動眼睡眠中,，在4個清醒狀態(tài)下活躍的大腦關(guān)鍵區(qū)域中,，ATP水平增加,，同時伴隨著大腦活性的全面降低。當大鼠處在清醒狀態(tài)時,，ATP水平是穩(wěn)定的,。此外，當輕輕觸碰正常睡眠時間過去3或6個小時的清醒老鼠,，ATP水平也不會增加,。因此，研究人員得出結(jié)論睡眠對于ATP能量補充是必需的,，保持大鼠處在清醒狀態(tài)則會阻止ATP水平上升,。
美國睡眠研究方面的專家Robert Greene博士認為，這項研究為"依賴于睡眠的能量上升對于促進能量補充的生物合成過程來說是必需的"這一理論提供了一個十分有趣的證據(jù),。另外Robert Greene博士就該發(fā)現(xiàn)提出了一個疑問，這項研究的作者提出睡眠過程中能量的上升和大腦中細胞活性的降低有關(guān),，但是這同樣也可能是一些其他的因素導(dǎo)致的，其中就包括大腦的細胞信號過程,。(生物谷Bioon.net)
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生物谷推薦原文出處：
The Journal of Neuroscience doi:10.1523/JNEUROSCI.1423-10.2010
Sleep and Brain Energy Levels: ATP Changes during Sleep
Markus Dworak, Robert W. McCarley, Tae Kim, Anna V. Kalinchuk, and Radhika Basheer
Laboratory of Neuroscience, Department of Psychiatry, Veterans Affairs Boston Healthcare System and Harvard Medical School, West Roxbury, Massachusetts 02132
Sleep is one of the most pervasive biological phenomena, but one whose function remains elusive. Although many theories of function, indirect evidence, and even common sense suggest sleep is needed for an increase in brain energy, brain energy levels have not been directly measured with modern technology. We here report that ATP levels, the energy currency of brain cells, show a surge in the initial hours of spontaneous sleep in wake-active but not in sleep-active brain regions of rat. The surge is dependent on sleep but not time of day, since preventing sleep by gentle handling of rats for 3 or 6 h also prevents the surge in ATP. A significant positive correlation was observed between the surge in ATP and EEG non-rapid eye movement delta activity (0.5–4.5 Hz) during spontaneous sleep. Inducing sleep and delta activity by adenosine infusion into basal forebrain during the normally active dark period also increases ATP. Together, these observations suggest that the surge in ATP occurs when the neuronal activity is reduced, as occurs during sleep. The levels of phosphorylated AMP-activated protein kinase (P-AMPK), well known for its role in cellular energy sensing and regulation, and ATP show reciprocal changes. P-AMPK levels are lower during the sleep-induced ATP surge than during wake or sleep deprivation. Together, these results suggest that sleep-induced surge in ATP and the decrease in P-AMPK levels set the stage for increased anabolic processes during sleep and provide insight into the molecular events leading to the restorative biosynthetic processes occurring during sleep.
