Project 2- Scammell

Scammell项目总结 在阻塞性睡眠呼吸暂停(OSA)患者中，唤醒起到了拯救生命的作用， 我们假设背外侧和桥脑脚被盖的神经元 核团(LDT/PPT)在觉醒的许多方面都起着重要作用，包括觉醒 从OSA的睡梦中醒来。我们的目标是确定LDT/PPT的具体功能 产生乙酰胆碱、谷氨酸和GABA的神经元；绘制解剖投射图 并研究它们如何影响关键靶区的活动， 调节睡眠/清醒行为和呼吸。我们将通过以下方式实现这些目标 光遗传学研究急性的、短暂的神经细胞活动的增加或减少 行为状态和专门使用设计者受体的药物合成 由特制药物(DREADD)激活，以检查持续数小时的变化。作为一名模特 OSA的许多实验将使用重复二氧化碳唤醒(RCA)方法来 检查睡眠期间对高碳酸血症的反应。 为了确定特定的LDT/PPT神经元是否足以唤醒，EEG 激活，以及对RCA的反应，我们将使用 HM3DREADD或通道视紫红质(ChR2)。为了确定特定的LDT/PPT神经元 是觉醒、脑电激活和对RCA的反应所必需的，我们将抑制 每类神经元使用HM4 DREADD或ARCHT，一种抑制性古紫质。 为了定义调节这些行为反应的关键LDT/PPT目标区域，我们将 应用条件性顺行和条件性方法对特定LDT/PPT神经元的MAP投射 逆行追踪；使用ChR2-确定哪些投射形成功能性突触 辅助电路映射(CRACM)；并确定哪些目标区域在功能上 最重要的是局部刺激或抑制谷氨酸和胆碱能神经 在每个目标区域使用ChR2或ARCHT的终端。 总而言之，这些多学科的实验将定义神经 特定类型的LDT/PPT神经元促进觉醒的机制， 阻塞性睡眠呼吸暂停小鼠模型的皮质激活和觉醒。这些研究的结果 实验应该大大提高我们对神经的科学知识 由于高碳酸血症而产生清醒和觉醒的机制，并最终 为阻塞性睡眠呼吸暂停症带来更好的治疗方法。

Scammell Project Summary In patients with obstructive sleep apnea (OSA), arousals play a life-saving role, and we hypothesize that neurons in the laterodorsal and pedunculopontine tegmental nuclei (LDT/PPT) play an essential role in many aspects of arousal, including arousals from sleep in OSA. Our goals are to determine the specific functions of the LDT/PPT neurons producing acetylcholine, glutamate and GABA; to map the anatomic projections of these cells; and to examine how they influence the activity of key target regions that regulate sleep/wake behavior and respiration. We will pursue these goals using optogenetics to examine acute, brief increases or decreases in neuronal activity within a behavioral state, and pharmacosynthetics using Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) to examine changes lasting hours. As a model of OSA, many experiments will use the Repetitive CO2 Arousal (RCA) method to examine responses to hypercapnia during sleep. To determine if specific LDT/PPT neurons are sufficient for wakefulness, EEG activation, and the response to RCA, we will activate each class of neurons using the hM3 DREADD or channelrhodopsin (ChR2). To determine if specific LDT/PPT neurons are necessary for wakefulness, EEG activation, and the response to RCA, we will inhibit each class of neurons using the hM4 DREADD or ArchT, an inhibitory archaerhodopsin. To define the key LDT/PPT target regions mediating these behavioral responses, we will map projections of specific LDT/PPT neurons using conditional anterograde and retrograde tracing; determine which projections form functional synapses using ChR2- Assisted Circuit Mapping (CRACM); and determine which target regions are functionally most important by focally stimulating or inhibiting glutamatergic and cholinergic nerve terminals in each target region using ChR2 or ArchT. Collectively, these multidisciplinary experiments will define the neural mechanisms through which specific types of LDT/PPT neurons promote wakefulness, cortical activation, and arousals in a mouse model of OSA. The results of these experiments should substantially improve our scientific knowledge of the neural mechanisms that generate wakefulness and arousals due to hypercapnia, and ultimately lead to better treatments for obstructive sleep apnea.