科学家发现了慢波睡眠中在大脑皮层中活跃的神经元,这可能对于治疗失眠症等睡眠疾病以及理解诸如情绪和记忆等依赖于睡眠的活动具有重要意义。Dmitry Gerashchenko及其同事报告说,包含了罕见的一组神经元的皮层在自然睡眠以及剥夺睡眠之后发生的恢复睡眠过程中是活跃的。这组作者发现了一种制造一氧化氮(NO)——这是一种调控大脑血流的因子——的特殊类型的皮层神经元,而且它们在小鼠、大鼠和仓鼠的慢波睡眠过程中在皮层中是活跃的。相关论文发表在美国《国家科学院院刊》(PNAS)上。
此前的研究假定,慢波活动(SWA)——正在睡眠的大脑的标志——与睡眠的恢复属性以及大脑的学习能力有关联。已经在前脑和下丘脑中发现了特别在睡眠过程中活跃的神经元的群体。然而,迄今为止,这个皮层在SWA中担任的角色仍然是一个谜,因为所有的皮层细胞被认为在慢波睡眠中都是静止的。这组作者提出,由于这些神经元也存在于人类大脑中,它们很可能也在人类的睡眠过程中活跃。(生物谷Bioon.com)
生物谷推荐原始出处:
PNAS,doi: 10.1073/pnas.0803125105,Dmitry Gerashchenko,Thomas S. Kilduff
Identification of a population of sleep-active cerebral cortex neurons
Dmitry Gerashchenko*, Jonathan P. Wisor*, Deirdre Burns*, Rebecca K. Reh†, Priyattam J. Shiromani‡, Takeshi Sakurai§, Horacio O. de la Iglesia†, and Thomas S. Kilduff*,¶
+Author Affiliations
*Biosciences Division, SRI International, Menlo Park, CA 94025;
†Department of Biology, University of Washington, Seattle, WA 98195-1800;
‡Department of Neurology, West Roxbury VA Medical Center and Harvard Medical School, 1400 VFW Parkway, West Roxbury, MA 02132; and
§Department of Molecular Neuroscience and Integrative Physiology, Kanazawa University, Kanazawa 920-8640, Japan
Edited by Sacha B. Nelson, Brandeis University, Waltham, MA, and accepted by the Editorial Board May 23, 2008 (received for review March 30, 2008)
Abstract
The presence of large-amplitude, slow waves in the EEG is a primary characteristic that distinguishes cerebral activity during sleep from that which occurs during wakefulness. Although sleep-active neurons have been identified in other brain areas, neurons that are specifically activated during slow-wave sleep have not previously been described in the cerebral cortex. We have identified a population of cells in the cortex that is activated during sleep in three mammalian species. These cortical neurons are a subset of GABAergic interneurons that express neuronal NOS (nNOS). Because Fos expression in these sleep-active, nNOS-immunoreactive (nNOS-ir) neurons parallels changes in the intensity of slow-wave activity in the EEG, and these neurons are innvervated by neurotransmitter systems previously implicated in sleep/wake control, cortical nNOS-ir neurons may be part of the neurobiological substrate that underlies homeostatic sleep regulation.