Cellular and Molecular Mechanisms of REM Sleep

描述(申请人提供)：这项研究的长期目标是进一步了解脑干细胞、分子和网络机制的快速眼动睡眠调节。具体地说，这一更新应用的目的是研究桥脚被盖胆碱能细胞室(CCC-PPT)和蓝斑背侧核(SubCD)在REM睡眠稳态调节中的作用的分子机制。这一假设的核心假设是，脑源性神经营养因子受体(原肌球蛋白相关激酶B[TrkB])和细胞外信号调节蛋白1/2(ERK1/2)信号在CCC-PPT和SubCD中的相互作用积极地调节REM睡眠和脑桥波(P波)活动的动态平衡。为了系统地检验这一假说，我们设计了三个特定的目标：1.检验以下假说：在选择性REM睡眠剥夺过程中，慢波睡眠的增加和CCC-PPT中BDNF表达的增加对REM睡眠的稳态驱动的发展至关重要，而在相同条件下，亚CD中BDNF表达的增加对P波活动的稳态调节至关重要。这一目标将通过测量增加的REM睡眠平衡驱动的不同强度下CCC-PPT、SubCD和一些控制区中与平衡驱动相关的BDNF水平的变化来实现。2.验证以下假设：CCC-PPT中BDNF TrkB受体和ERK1/2信号之间的相互作用对REM睡眠的稳态调节至关重要，而亚CD中的这种相互作用对P波活动的稳态调节至关重要。为了验证这一假设，在选择性REM睡眠剥夺时期的开始，我们将BDNF TrkB受体抑制剂、ERK1/2激活抑制剂或赋形剂对照应用于大鼠的CCC-PPT或SubCD，以阻止REM睡眠增加的动态平衡驱动。3.验证以下假设：在杂合子BDNF基因敲除(BDNF/-)大鼠中，CCC-PPT中BDNF的产生减少减弱了对REM睡眠的稳态调节，而SubCD中的BDNF产生的减少则减弱了对P波活动的稳态调节。为了验证这一假设，在选择性REM睡眠剥夺时期的开始，我们将BDNF应用于BDNF/-大鼠的CCC-PPT或SubCD。所有这些实验都将在成年、自由活动的大鼠身上进行。我们相信，这些研究的结果将扩大关于REM睡眠调节的基本神经生物学机制的前沿知识。此外，这些结果将首次启动一个新的研究领域，旨在了解REM睡眠个体生理迹象的局部细胞和分子平衡调节机制。我们相信，这些研究的结果将有助于阐明许多精神和神经疾病(如内源性抑郁症、精神分裂症、阿尔茨海默氏症、亨廷顿氏症、帕金森氏症和中风)的REM睡眠稳态调节功能障碍的神经病理机制，并将帮助我们设计治疗干预措施来消除这些功能障碍。

DESCRIPTION (provided by applicant): The long-term objective of this research is to further our understanding of brainstem cellular, molecular, and network mechanisms of REM sleep regulation. Specifically, the goal of this renewal application is to investigate the molecular mechanisms within the cholinergic cell compartment of the pedunculopontine tegmentum (CCC-PPT) and dorsal subcoeruleus nucleus (SubCD) with respect to their roles in homeostatic regulation of REM sleep. The central hypothesis of this proposal is that homeostatic regulation of REM sleep and phasic pontine- wave (P-wave) activity are actively regulated by the interaction between brain-derived neurotrophic factor (BDNF) receptors (tropomyosin-related kinase B [TrkB]) and extracellular signal-regulated kinase1/2 (ERK1/2) signaling in the CCC-PPT and SubCD. Three specific aims have been designed to systematically test this hypothesis: 1. Test the hypothesis that during selective REM sleep deprivation, increased slow-wave sleep and increased expression of BDNF in the CCC-PPT are critical for the development of homeostatic drive for REM sleep, and under the same conditions, increased BDNF expression in the SubCD is critical for the homeostatic regulation of P-wave activity. This goal will be achieved by measuring homeostatic drive-associated changes in BDNF levels in the CCC-PPT, SubCD, and in a number of control areas at different intensities of increased REM sleep homeostatic drive. 2. Test the hypothesis that the interaction between BDNF TrkB receptors and ERK1/2 signaling in the CCC-PPT is critical for the homeostatic regulation of REM sleep, and that this same interaction in the SubCD is critical for the homeostatic regulation of P-wave activity. To test this hypothesis, at the beginning of a selective REM sleep deprivation period we will apply a BDNF TrkB receptor inhibitor, ERK1/2 activation inhibitor, or vehicle control into either the CCC-PPT or SubCD of rats, in order to block the increased homeostatic drive for REM sleep. 3. Test the hypothesis that, in heterozygous BDNF knockout (BDNF+/-) rats, decreased BDNF production in the CCC-PPT attenuates homeostatic regulation of REM sleep, and decreased BDNF production in the SubCD attenuates homeostatic regulation of P-wave activity. To test this hypothesis, at the beginning of the selective REM sleep deprivation period we will apply BDNF either into the CCC-PPT or SubCD of BDNF+/- rats. All of these experiments will be performed on adult, freely moving rats. We believe that the results of these studies will extend the leading edge of knowledge on the basic neurobiological mechanisms of REM sleep regulation. Also, for the first time, these results will launch a new area of investigation aimed at understanding the localized cellular and molecular mechanisms of homeostatic regulation of individual physiological signs of REM sleep. We believe that the results of these studies will shed light on the neuro-pathological mechanisms of REM sleep homeostatic regulatory dysfunctions in a number of psychiatric and neurological disorders (e.g., endogenous depression, schizophrenia, Alzheimer's, Huntington's, Parkinson's, and stroke), and will help us to design therapeutic interventions to eliminate these dysfunctions.