Opioid effects on respiratory-controlling pontine neurons

 描述(申请人提供)：阿片类药物过量死亡主要是由于呼吸抑制，但对阿片类药物对呼吸控制神经元的细胞机制知之甚少。长期目标是成为一名独立的终身教职调查员，研究阿片类药物呼吸抑制作用的机制。这项提议旨在补充候选人在阿片类药物药理学和脑片电生理学方面的背景，并提供实现这一目标所需的呼吸生理学方面的额外知识和技术技能。阿片类药物被证明通过中枢呼吸网络的多个区域抑制呼吸，包括延髓的前Botzinger复合体和脑桥的Kolliker-Fuse(KF)核。尽管阿片类药物已被证明抑制Botzinger前神经元，但阿片类药物在KF中的作用机制尚未被研究，因此尚不清楚。这项提议的直接目标是确定阿片类药物如何调节KF神经元来改变呼吸。假说是阿片类药物会使KF神经元超极化，从而扰乱呼吸网络。这一假说将通过记录(1)来自脑片中的KF神经元和(2)来自KF神经元和呼吸神经的原位准备来验证，该原位制备具有完整的呼吸网络和活体呼吸周期。在目标1中，来自原位制备的细胞外记录将识别被阿片类药物抑制的KF神经元的呼吸表型。这项新技能将通过与Ana Abdala博士、Julian Paton博士(布里斯托尔大学)和Mary Heinricher博士(OHSU)协商学习，将是应聘者职业发展的关键组成部分。鉴于对阿片类药物的呼吸抑制作用缺乏耐受性，目标2的假设是，Mu阿片受体对KF神经元几乎没有耐受性和脱敏作用。目标3将在该奖项的独立阶段进行，目的是确定5-HT1A受体的位置和功能，这些受体可以逆转阿片类药物诱导的呼吸抑制。一种治疗策略，如5-HT1A激动剂，可以逆转呼吸抑制，但保持止痛不变，将是一个重大的进步。约翰·威廉姆斯是世界著名的电生理学家，他曾指导20多名科学家实现独立的职业生涯，他的指导将提供脑片电生理学方面的持续培训，并发展管理独立研究小组的技能。呼吸生理学方面的新知识将从合作导师John Bissonnette(OHSU)那里获得，他在呼吸的神经控制方面拥有30多年的经验。新的知识、技术技能、持续的生产力和实用的职业指导将使候选人处于竞争地位，成为从细胞和网络角度研究阿片类药物呼吸抑制效应的终身教职助理教授。

 DESCRIPTION (provided by applicant): Death from opioid overdose is primarily due to respiratory depression, yet little is known about the cellular mechanisms of opioids on respiratory-controlling neurons. The long-term goal is to become an independent tenure-track investigator studying the mechanisms responsible for the respiratory depressant effects of opioids. This proposal has been designed to supplement the candidate's background in opioid pharmacology and brain slice electrophysiology and provide the additional knowledge and technical skills in respiratory physiology required to accomplish this goal. Opioids have been shown to suppress respiration through multiple areas of the central respiratory network, including the preBotzinger complex in the medulla and the Kolliker-Fuse (KF) nucleus in the pons. Although opioids have been shown to inhibit preBotzinger neurons, the mechanism of opioid actions in the KF has not been studied and is therefore unknown. The immediate goal of this proposal is to determine how opioids modulate KF neurons to alter respiration. The hypothesis is that opioids hyperpolarize KF neurons to disrupt the respiratory network. This hypothesis will be tested by recording (1) from KF neurons in brain slices and (2) from KF neurons and respiratory nerves in an in situ preparation with intact respiratory network and in vivo respiratory cycle. In Aim 1, extracellular recording from the in situ preparation will identif the respiratory phenotype of KF neurons inhibited by opioids. This new technical skill will be learned through consultation with Drs. Ana Abdala and Julian Paton (University of Bristol) and Mary Heinricher (OHSU) and will be a critical component of the candidate's career development. Given the lack of tolerance to the respiratory depressant effect of opioids, the hypothesis of Aim 2 is that there will be very little tolerance and desensitization of mu opioid receptors on KF neurons. The goal of Aim 3, which will be performed during the independent phase of this award, is to identify the location and function of 5-HT1A receptors that can reverse opioid-induced respiratory depression. A therapeutic strategy such as 5-HT1A agonists that can reverse respiratory depression, but leave analgesia intact would be a significant advance. Mentorship from John Williams, who is a world-renowned electro physiologist and has mentored over 20 scientists to achieve independent careers, will provide continued training in brain slice electrophysiology and development of skills to manage an independent research group. New knowledge in respiratory physiology will be acquired from co-mentor John Bissonnette (OHSU), who has over 30 years of experience in neural control of respiration. The new knowledge, technical skills, continued productivity and practical career guidance will place the candidate in competitive position to become a tenure-track assistant professor studying the respiratory depressant effects of opioids from a cellular and network perspective.