Orexins in Rapid Eye Movement Sleep Control.

描述（由申请人提供）：食欲素/下丘脑分泌素是对正常睡眠-觉醒至关重要的下丘脑神经肽。有相当多的证据表明食欲素与猝倒/嗜睡症有关，这可能被视为快速眼动睡眠障碍。虽然食欲素神经元的细胞体只局限于下丘脑外侧，但食欲素神经元发出广泛的投射，并以控制睡眠-觉醒的重要大脑区域为目标。这个研究项目的主要目标是了解食欲素控制快速眼动睡眠的细胞和分子机制，从而为理解和治疗包括嗜睡症在内的人类睡眠障碍提供坚实的基础。我们将使用多学科方法的新组合，包括在体内使用小干扰RNA （siRNA）敲除脑干口桥/腹侧蓝下区（PNO）区域的食欲素II型受体，定量实时PCR验证敲除和睡眠-觉醒的电记录。我们的假设是，食欲素通过作用于PNO局部gaba能神经元上的食欲素II型受体来防止快速眼动睡眠和与快速眼动相关的肌肉张力失调的发生。我们将在自由行为大鼠的PNO中使用siRNA对抗食欲素II型受体，预测快速眼动睡眠时间的增加以及偶尔的猝倒/睡眠发作性快速眼动样发作。我们进一步预测，外源性给药促食欲素会增加对照组大鼠（盐水和炒siRNA处理）的清醒程度，但siRNA处理大鼠的反应会减弱。相比之下，在siRNA处理和对照组（盐水处理和混杂siRNA处理）大鼠中，苯酚给药PNO会诱导短潜伏期的快速眼动睡眠。本研究计划的主要目的是了解食欲素控制睡眠-觉醒的细胞和分子机制，从而为理解和治疗包括嗜睡症在内的人类睡眠障碍提供坚实的基础。

DESCRIPTION (provided by applicant): Orexins/Hypocretins are hypothalamic neuropeptides that are critical for normal sleep-wakefulness. There is considerable evidence linking orexins to cataplexy/narcolepsy, which may be regarded as REM sleep disorders. While the cell bodies of orexin neurons are exclusively localized in the lateral hypothalamus, orexin neurons send widespread projections and target brain regions that are important in sleep- wakefulness control. The broad objective of this program of research is to understand the cellular and molecular mechanisms by which orexin control REM sleep and thereby to provide a sound basis for the understanding and treatment of human sleep disorders, including narcolepsy. We will use novel combinations of multi- disciplinary methods including the in vivo use of small interfering RNA (siRNA) for knockdowns of orexin type II receptor in the pontis oralis/ventral subcoeruleus region (PNO) region of the brainstem with quantitative real time PCR verification of knockdowns and electrographic recording of sleep-wakefulness. Our hypothesis is that orexin prevents the occurrence of REM sleep and REM related muscle atonia by its action on orexin type II receptors on local GABAergic neurons in the PNO. We will administer siRNA against orexin type II receptor in the PNO in freely behaving rats, predicting an increase in the amount of time spent in REM sleep along with occasional cataplexy/sleep-onset REM-like episodes. We further predict that exogenous administration of orexins to the PNO will increase wakefulness in control (saline and scrambled siRNA treated) rats but will have a blunted response in the siRNA treated rats. In contrast, carbachol administration to the PNO will induce REM sleep with short latency in both siRNA and control (saline and scrambled siRNA treated) rats. PUBLIC HEALTH RELEVANCE The broad objective of this research program is to understand the cellular and molecular mechanisms by which orexins control sleep-wakefulness and thereby to provide a sound basis for the understanding and treatment of human sleep disorders, including narcolepsy.