Project 2

项目2

• 批准号: 10491088
• 负责人: THOMAS E SCAMMELL
• 金额: $ 43.46万
• 依托单位: BETH ISRAEL DEACONESS MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-07-01 至 2025-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10491088
• 关键词: Address; Affect; Afferent Pathways; Air Movements; Anatomy; Arousal; Automobile Driving; Brain Stem; Calcitonin Gene-Related Peptide; Calcium; Continuous Positive Airway Pressure; Drowsiness; Electroencephalography; Exposure to; Fiber; Frequencies; Goals; Hypercapnia; Hypothalamic structure; Image; In Situ Hybridization; In Vitro; Lateral; Maps; Measures; Mechanoreceptors; Methods; Mus; Neurons; Obstructive Sleep Apnea; Pathway interactions; Patients; Pattern; Persons; Pharmaceutical Preparations; Pharmacology; Photometry; Prosencephalon; Recurrence; Signal Pathway; Signal Transduction; Sleep; Sleep Apnea Syndromes; Sleep Deprivation; Sleep disturbances; Slice; Synapses; Techniques; Tidal Volume; Time; airway obstruction; experimental study; improved; method development; multidisciplinary; neurochemistry; neuromechanism; parabrachial nucleus; preservation; prevent; receptor; receptor expression; receptor function; respiratory; response; single cell sequencing; single-cell RNA sequencing; translational impact; ventilation

Project Summary/Abstract – Project 2 In people with obstructive sleep apnea (OSA), airflow obstruction results in hypercarbia and other signals that increase ventilation, dilate the airway, and also trigger cortical arousals from sleep. Current therapies such as CPAP focus on airway opening, but compliance with these therapies is poor, and many patients continue to have daytime sleepiness. As recurrent arousals from sleep contribute to daytime sleepiness and other consequences of OSA, new methods that maintain sleep in OSA without disrupting ventilation would address an important, unmet need in OSA treatment. In the last cycle of this P01, Dr. Saper’s group (Project 1) showed that calcitonin gene-related peptide (CGRP) neurons of the lateral parabrachial nucleus are necessary for cortical arousals in response to hypercapnia. Specifically, inactivation of PBCGRP neurons substantially delays or eliminates cortical arousals in response to hypercapnia without blunting ventilatory responses. Thus, the PBCGRP neurons are essential for driving cortical arousals, but they are not necessary for ventilatory responses to hypercapnia. We hypothesize that activation of inhibitory inputs to the PBCGRP neurons will delay or eliminate cortical arousals to hypercapnia without altering ventilatory responses. Our Aims seek to identify these inputs and their receptors on the PBCGRP neurons, with the ultimate goal of selectively reducing activity in the PBCGRP neurons to prevent cortical arousals while preserving ventilatory responses. This Project synergizes well with Projects 1, 3, and 4 that seek to enhance ventilatory responses to hypercapnia in mice, and Project 5 which seeks to identify pharmacological methods to improve OSA in people. We will first use conditional and conventional tracing methods to identify afferents to the PBCGRP neurons, and then we will use Channelrhodopsin-assisted circuit mapping (CRACM) to establish synaptic connectivity. Using single cell sequencing techniques, we will then identify receptors expressed by the PBCGRP neurons, and confirm receptor expression using in situ hybridization and in vitro calcium imaging. We will then use fos and fiber photometry to determine which afferent pathways to the PBCGRP neurons are sleep-active. Last, we will determine whether signaling through inhibitory inputs to the PBCGRP neurons delays or eliminates cortical arousals triggered by brief period of hypercapnia. We will measure the latency to cortical arousal after hypercapnia in combination with photostimulation of inhibitory inputs to the PBCGRP neurons and then with pharmacological inhibition of the PBCGRP neurons. Collectively, these multidisciplinary experiments will identify crucial anatomical and neurochemical inputs to the PBCGRP neurons that should provide new pharmacological opportunities for maintaining sleep in OSA without inhibiting airway opening.

项目摘要/摘要 - 项目2 在有阻塞性睡眠呼吸暂停（OSA）的人中，气流阻塞会导致高碳和其他信号 这会增加通风，扩张气道，并引发睡眠中的皮质唤醒。当前的疗法 由于CPAP专注于气道开口，但遵守这些疗法很差，许多患者继续 有白天的嗜睡。随着睡眠的反复唤醒有助于白天的嗜睡和其他 OSA的后果，在不干扰通风的情况下保持睡眠的新方法将解决 OSA处理中的重要，未满足的需求。 在该P01的最后一个周期中，Saper博士的组（项目1）表明降钙素基因相关肽 （CGRP）侧面止痛核的神经元对于皮质唤醒是必要的 高碳酸盐。具体而言，PBCGRP神经元的失活大大延迟或消除了皮质唤醒 对超脑的反应，而无需钝化通气反应。那就是PBCGRP神经元对于 驱动皮质唤醒，但这对于对高碳酸盐的通风反应并不是必需的。我们假设 向PBCGRP神经元的抑制输入激活将延迟或消除皮质唤醒到高碳酸盐 没有改变通气反应。 我们的目标旨在在PBCGRP神经元上识别这些输入及其受体，其最终目标是 有选择地降低PBCGRP神经元的活性，以防止皮质唤醒，同时保持通风 回答。该项目与旨在增强通气反应的项目1、3和4协同效果 小鼠中的高碳酸脂蛋白，以及旨在识别改善OSA的药物方法的项目5 人们。我们将首先使用条件和常规跟踪方法来识别PBCGRP的传入 神经元，然后我们将使用ChannelRhopopsin辅助电路映射（CRACM）建立突触 连接性。然后，我们将使用单细胞测序技术识别PBCGRP表达的受体 神经元，并使用原位杂交和体外钙成像证实受体表达。然后我们会 使用FOS和纤维光度法确定PBCGRP神经元的传入途径是睡眠活性的。 最后，我们将确定通过抑制性输入对PBCGRP神经元延迟还是消除 皮质唤醒是由短期高碳酸酶触发的。我们将测量在 高碳酸血症结合对PBCGRP神经元的抑制性输入的光刺激，然后与 PBCGRP神经元的药理抑制作用。 总的来说，这些多学科实验将确定至关重要的解剖学和神经化学输入 PBCGRP神经元应该提供新的药物机会来维持OSA的睡眠 不抑制气道开口。