Volatile Anesthetic Regulation of TASK Tandem Pore Potassium Channels

描述(由申请人提供)：本提案描述了一项为期5年的培训计划，旨在培养一名挥发性麻醉机制的独立调查员。首席研究员是哈佛医学院麻醉系的一名教员，具有电生理学背景，他将获得足够的神经科学和药理学的新知识和技能，足以领导他自己的独立研究计划。这项工作将在马萨诸塞州总医院的Mallinckrodt药理学研究单位进行，重点是挥发性麻醉机制。我们的特定目的将检验这一新的假设，即挥发性麻醉药通过抑制基础或激动剂介导的Galpha-Q蛋白偶联受体(GqPCR)的活性间接增强TASK-3的功能。TASK-3串联孔钾通道是一种挥发性麻醉剂增强、pH和低氧抑制的离子通道。TASK-3在中枢神经系统和外周组织中广泛表达，并在多种类型的细胞中发挥化学传感作用，包括那些参与呼吸调节的细胞。GqPCR激活也抑制了TASK-3的功能。中枢神经系统中的GqPCRs调节记忆、觉醒和意识，而外周则是调节平滑肌张力的重要因素。许多GqPCRs的功能被挥发性麻醉剂抑制。为了验证我们的假设，我们将使用非洲爪哇卵母细胞的双电极电压钳或费舍尔大鼠甲状腺细胞异源表达TASK-3通道和m1或m3 GqPCRs和Galpha-Q蛋白的研究。我们还将使用切除的膜片钳方法，以及包括RNA干扰和定点突变在内的几种分子生物学技术。长期目标：该项目将阐明挥发性麻醉剂增强任务通道的分子机制。公共卫生相关性这项工作将有助于建立指导开发不影响呼吸的更安全的麻醉药的原则，并进一步阐明这些药物诱导麻醉的机制。

DESCRIPTION (provided by applicant): This proposal describes a 5-year training program for the development of an independent investigator in volatile anesthetic mechanisms. The principal investigator is a faculty member in the Department of Anesthesia, Harvard Medical School, with a background in electrophysiology, who will acquire new knowledge and skills in neuroscience and pharmacology sufficient to lead his own independent research program. Work will be conducted in the Mallinckrodt Pharmacology Research Unit at Massachussets General Hospital which focuses on volatile anesthetic mechanisms. Our SPECIFIC AIMS wil test the novel hypothesis that volatile anesthetics potentiate TASK-3 function indirectly by inhibition of basal or agonst-mediated Galpha-q protein coupled receptor (GqPCR) activity. The TASK-3 tandem pore potassium channel is a volatile anesthetic-potentiated and pH- and hypoxia-inhibited ion channel. TASK-3 is widely expressed in the central nervous system and in peripheral tissue and has a role in chemosensing in a variety of cell types, including those involved in regulation of breathing. TASK-3 function is also inhibited by GqPCR activation. GqPCRs in the CNS regulate memory, wakefulness, and consciousness and peripherally are important regulators of smooth muscle tone. The function of many GqPCRs are inhibited by volatile anesthetics. To test our hypothesis we will use two-electrode voltage clamp of Xenopus oocytes or Ussing Chamber studies of Fischer Rat Thyroid cells heterologously expressing TASK-3 channels and ml or m3 GqPCRs and Galpha-q protein. We will also employ the excised patch-clamp method, and several molecular biology techniques including RNA interference and site-directed mutagenesis. LONG TERM GOALS: This project will clairfy the molecular mechanism by which volatile anesthetics potentiate TASK channels. PUBLIC HEALTH RELEVANCE This work will help establish principles to guide development of safer anesthetic drugs that do not effect breathing and further elucidate the mechanism by which these drugs induce anesthesia.