小柯机器人

美国哈佛大学医学院Stephen D. Liberles团队的研究系统描绘了迷走神经元的遗传图谱并揭示了其呼吸道保护功能。该研究于2020年4月6日在线发表在《细胞》杂志上。

研究人员发现了罕见的咽部神经支配神经元（每只小鼠约100个神经元），可以保护呼吸道免受攻击。研究人员利用遗传工具揭示了广泛涵盖迷走神经/舌咽感觉神经元图谱，以描绘、减少和控制特定的传入人群。迷走神经元P2RY1的光遗传学激活引起协调气道防御途径包括：呼吸暂停、声带内收、吞咽和呼气反射。迷走神经元P2RY1的缺失消除了对喉水和酸刺激的保护性反应。

利用解剖图研究人员发现了许多喉部末梢类型，并发现P2RY1神经元形成了附有喉味蕾的小体末梢。上皮细胞是主要的气道前哨，其通过ATP与次级神经元P2RY1进行信息传递。这些发现为迷走神经的气道防御功能和一般的分子/遗传学路线图绘制提供了机制方面的见解。

据介绍，感觉神经元启动防御反射，以确保呼吸道完整性。喉部神经元功能异常会危及生命，引起肺误吸、吞咽困难和窒息；但人类对与其相关的感觉途径仍知之甚少。

附：英文原文

Title: An Airway Protection Program Revealed by Sweeping Genetic Control of Vagal Afferents

Author: Sara L. Prescott, Benjamin D. Umans, Erika K. Williams, Rachael D. Brust, Stephen D. Liberles

Issue&Volume: 2020-04-06

Abstract: Sensory neurons initiate defensive reflexes that ensure airway integrity. Dysfunctionof laryngeal neurons is life-threatening, causing pulmonary aspiration, dysphagia,and choking, yet relevant sensory pathways remain poorly understood. Here, we discoverrare throat-innervating neurons (～100 neurons/mouse) that guard the airways againstassault. We used genetic tools that broadly cover a vagal/glossopharyngeal sensoryneuron atlas to map, ablate, and control specific afferent populations. Optogeneticactivation of vagal P2RY1 neurons evokes a coordinated airway defense program—apnea,vocal fold adduction, swallowing, and expiratory reflexes. Ablation of vagal P2RY1neurons eliminates protective responses to laryngeal water and acid challenge. Anatomicalmapping revealed numerous laryngeal terminal types, with P2RY1 neurons forming corpuscularendings that appose laryngeal taste buds. Epithelial cells are primary airway sentinelsthat communicate with second-order P2RY1 neurons through ATP. These findings providemechanistic insights into airway defense and a general molecular/genetic roadmap forinternal organ sensation by the vagus nerve.

DOI: 10.1016/j.cell.2020.03.004

Source: https://www.cell.com/cell/fulltext/S0092-8674(20)30266-X