Project 1

项目1

• 批准号: 10491085
• 负责人: CLIFFORD B SAPER
• 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/10491085
• 关键词: Animals; Apnea; Arousal; Brain; Calcium; Carbon Dioxide; Cardiovascular system; Cells; Chloride Channels; Clozapine; Cognitive; Complex; Data; Dilator; Dorsal; Dose; Electroencephalography; Exposure to; FOXP2 gene; Fiber; Fire - disasters; Goals; Human; Hypercapnia; Hypoxia; Image; Impaired cognition; Individual; Lateral; Measures; Metabolic; Monitor; Motor; Mus; Muscle; Muscle Tonus; Neurons; Nucleus solitarius; Obstructive Sleep Apnea; Outcome; Oxides; Patients; Pattern; Pharmacology; Photometry; Play; Population; Prosencephalon; Ramp; Respiratory Muscles; Respiratory System; Rodent; Role; Signal Transduction; Site; Sleep; Sleep Apnea Syndromes; Sleep Deprivation; Sleep Fragmentations; Stimulus; Testing; Tidal Volume; airway obstruction; genioglossus muscle; hypoglossal nucleus; indexing; individual response; lens; optogenetics; parabrachial nucleus; photoactivation; preBotzinger complex; prevent; receptor; respiratory; response; therapy design; transcription factor; ventilation

Summary/Abstract: Project 1 Patients with obstructive sleep apnea (OSA) may have hundreds of cycles over the night of loss of airway dilator motor tone and airway obstruction, followed by apnea, which is ended by an arousal, in which there is EEG desynchronization accompanied by return of airway dilator muscle tone, opening of the airway, and re- established ventilation. The EEG arousals cause sleep fragmentation and loss, resulting in cognitive impairment, and metabolic and cardiovascular consequences. We hypothesize that by augmenting brain circuits that keep the airway open while suppressing the EEG arousals, we can prevent these outcomes. We previously demonstrated that the EEG arousal to CO2 depends upon a population of CGRP neurons in the parabrachial nucleus (PBCGRP neurons). We now have identified a population of neurons expressing the transcription factor FoxP2 (PBFoxP2 neurons) which are just lateral to the PBCGRP neurons and which appear to be responsible for much of the increase in ventilation and in EMG tone of the genioglossus muscle (GG-EMG), an airway dilator, during CO2 exposure. In Specific Aim 1 we plan to use Channelrhodopsin2 to optogenetically activate PBFoxP2 neurons at baseline and during CO2 arousal, and will measure changes in respiratory rate, tidal volume, minute ventilation, and GG-EMG. We hypothesize that we can increase the respiratory response to CO2 in this way. We will then activate specific terminal fields of the PBFoxP2 neurons in the dorsal (nucleus of the solitary tract, hypoglossal nucleus) and ventral (preBötzinger complex, caudal ventrolateral medulla) to determine which of these contribute to the overall respiratory response. In Specific Aim 2 we will use ArchaerhodopsinT to inhibit the PBFoxP2 neurons or their terminal fields in the medulla, at baseline and during CO2 exposure, to see which are required for the respiratory response to CO2. Specific Aim 3 will use GCaMP6 calcium imaging to examine the responses of PBFoxP2 and PBCGRP neurons to CO2 arousal. We will examine this initially with fiber photometry, but then will record the responses of individual FoxP2 or CGRP neurons in the PB during CO2 arousal and other stimuli, to determine whether there are subsets within these groups that respond to specific classes of stimuli. Finally, in Specific Aim 4, we will use chemogenetics to enhance the firing of the PBFoxP2 neurons with the hM3Dq excitatory receptor and to suppress the firing of the PBCGRP neurons with the hGlyR inhibitory receptor. We plan then to combine these approaches in single animals to provide a proof of principle that selective and simultaneous activation of PBFoxP2 neurons and inhibition of PBCGRP neurons can allow a vigorous respiratory response, including increased GG-EMG in response to CO2 during sleep, without resulting in EEG arousal.

摘要/摘要：项目1 阻塞性睡眠呼吸暂停（OSA）患者可能有数百个周期的夜间气道丧失 扩张器运动张力和气道阻塞，然后是呼吸暂停，最后是觉醒，其中有 EEG去极化伴随气道扩张肌张力恢复、气道开放和再狭窄。 建立通风。EEG唤醒引起睡眠片段化和丧失，导致认知障碍。 以及代谢和心血管后果。我们假设通过增强大脑 保持气道开放同时抑制EEG唤醒的电路，我们可以防止这些结果。我们 先前证明，EEG对CO2的唤醒取决于大脑皮层中CGRP神经元的数量， 臂旁核（PBCGRP神经元）。我们现在已经确定了一群表达 转录因子FoxP 2（PBFoxP 2神经元），其位于PBCGRP神经元的侧面， 负责增加通气量和颏舌肌的EMG张力（GG-EMG）， 呼吸道扩张器，在二氧化碳暴露期间。在具体目标1中，我们计划使用视紫红质2来 在基线和CO2唤醒期间，光遗传学激活PBFoxP 2神经元，并将测量 呼吸率、潮气量、每分钟通气量和GG-EMG。我们假设我们可以增加 对二氧化碳的呼吸反应。然后，我们将激活PBFoxP 2神经元的特定终末区域， 背侧（孤束核，舌下神经核）和腹侧（前Bötzinger复合体，尾侧 延髓腹外侧）以确定这些中的哪些对整体呼吸反应有贡献。在特定 目的2：利用古紫质T抑制延髓PBFoxP 2神经元或其终末野， 基线和CO2暴露期间，以了解对CO2的呼吸反应所需的条件。具体 目的3：应用GCaMP 6钙离子成像技术，观察PBFoxP 2和PBCGRP神经元对CO2的反应 兴奋我们将首先用纤维光度法对此进行检查，然后记录个体的反应。 在CO2唤醒和其他刺激过程中，PB中的FoxP 2或CGRP神经元，以确定是否有 这些群体中对特定刺激类别做出反应的子集。最后，在具体目标4中，我们将使用 化学遗传学增强PBFoxP 2神经元与hM 3Dq兴奋性受体的放电， 用hGlyR抑制性受体抑制PBCGRP神经元的放电。然后我们计划将这些联合收割机 方法在单一的动物提供了一个原则的证明，选择性和同时激活的 PBFoxP 2神经元和PBCGRP神经元的抑制可以允许剧烈的呼吸反应，包括 在睡眠期间对CO2的反应增加了GG-EMG，而不会导致EEG唤醒。