Converting the sodium-potassium pump into a shutdown channel

将钠钾泵转变为关闭通道

基本信息

  • 批准号:
    RGPIN-2017-04624
  • 负责人:
  • 金额:
    $ 1.89万
  • 依托单位:
  • 依托单位国家:
    加拿大
  • 项目类别:
    Discovery Grants Program - Individual
  • 财政年份:
    2022
  • 资助国家:
    加拿大
  • 起止时间:
    2022-01-01 至 2023-12-31
  • 项目状态:
    已结题

项目摘要

Central neurons undergo spreading depolarization (SD) which shuts down brain function during acute metabolic demand. SD migrates across gray matter at 1-5 mm/min and has evolved in insects (and perhaps in the vertebrates) to induce brain silence under the stress of anoxia, head injury or sudden temperature change. SD is behaviorally protective by reducing movement but can kill neurons if it lasts many minutes. SD immediately follows failure of the Na/K ATPase but the molecular mechanism linking it the massive inward current driving SD is unknown and elusive. Blockade of voltage- or ligand-gated channels does not prevent the SD-like `anoxic` depolarization (AD). The molecular action the marine poison (palytoxin, Ptox) is known to specifically bind the Na/K pump at picomolar amounts, converting it from an ATP-requiring transporter to an open cationic channel. The sudden Na+ influx and K+ efflux we show emulates SD at a mere 10-100 nM in live brain slices of mouse or rat. Our hypothesis is that severe metabolic stress likewise converts the Na/K ATPase into a channel that drives SD, evoking the neuronal shutdown that is prevalent across animal classes. Thus the molecular action of Ptox can provide insight to CNS shutdown. The proposal has 3 Objectives: 1) Show with membrane patch recording by our HQP Peter G. that the Na/K ATPase opens to drive SD in amphibian and mammalian neurons of the higher brain. Direct demonstration of pump conversion to a channel requires recording across membrane patches from neurons. A Ptox-evoked 12 pS single channel conductance represents opening of a single pump transporter. 2) Demonstrate that conversion from pump to channel also drives SD in locust and Drosophilia where the molecular details of SD can be assessed in a large cohort using genetically variable strains. With the expertise of HQP Dr. Kristin S. we will extend patch experiments to insect brain. 3) Our pilot data from rat show SD is evoked by rapid temperature shifts to 40 or to 13oC, similar to heat- and chill-coma in insects. We will study brain slices from homeotherms under variable temperature, simulating poikilothermy to directly compare with naturally cold-blooded animals such as frog and insect. Shutdown elicited by SD reduces oxidative injury and bypasses partial depolarization that drives epileptiform/spastic activity. As well SD inactivates both Na+ channels...and the animal itself. But in homeotherms this immediate behavioral protection lasts only minutes and quickly leads to neuronal death, a process we do not understand. My Canadian lab together with my 3 HQPs represent the first neuroscience facility to directly study the CNS Na/K pump and the channels that open as it fails. We will identify the SD channel by showing a) it activates under metabolic stress; b) it is not blocked by inhibitors of standard channels across animal species; and c) it may share properties similar to the pump channel induced by Ptox.
中枢神经元经历扩散去极化(SD),其在急性代谢需求期间关闭脑功能。SD以1-5 mm/min的速度穿过灰质,并在昆虫(可能在脊椎动物中)中进化,以在缺氧、头部受伤或温度突然变化的压力下诱导大脑沉默。SD通过减少运动来保护行为,但如果持续数分钟,则会杀死神经元。SD紧随Na/K ATP酶的失效,但将其与驱动SD的大量内向电流联系起来的分子机制是未知的和难以捉摸的。阻断电压门控或配体门控通道并不能阻止SD样“缺氧”去极化(AD)。已知海洋毒物(海葵毒素,Ptox)的分子作用是特异性结合皮摩尔量的Na/K泵,将其从需要ATP的转运蛋白转化为开放的阳离子通道。我们显示的突然Na+流入和K+流出模拟了小鼠或大鼠活脑切片中仅10-100 nM的SD。我们的假设是,严重的代谢应激同样将Na/K ATP酶转化为驱动SD的通道,引起在动物类中普遍存在的神经元关闭。因此,Ptox的分子作用可以为CNS关闭提供见解。 该提案有3个目标:1)显示与膜补丁记录由我们的HQP彼得G。在两栖动物和哺乳动物的高级脑神经元中,Na/K ATP酶打开以驱动SD。泵转换为通道的直接演示需要记录来自神经元的跨膜补丁。Ptox诱发的12 pS单通道电导表示单泵转运蛋白的打开。2)证明从泵到通道的转换也驱动蝗虫和果蝇中的SD,其中SD的分子细节可以使用遗传可变菌株在大型队列中进行评估。凭借HQP博士的专业知识,我们将把贴片实验扩展到昆虫大脑。3)我们从大鼠身上获得的初步数据显示,SD是由温度快速变化到40或13 ℃引起的,类似于昆虫的热昏迷和冷昏迷。我们将在变温条件下研究恒温动物的脑切片,模拟变温,直接与青蛙、昆虫等自然界的冷血动物进行比较。 SD引起的癫痫可减少氧化损伤,并绕过驱动癫痫样/痉挛活动的部分去极化。同时,SD使两个Na+通道失活…和动物本身。但在恒温动物中,这种即时的行为保护只持续几分钟,很快就会导致神经元死亡,这是一个我们不了解的过程。我的加拿大实验室和我的3个HQP代表了第一个直接研究CNS Na/K泵和当它失败时打开的通道的神经科学设施。我们将通过以下方式鉴定SD通道:a)它在代谢应激下激活; B)它不被动物物种中标准通道的抑制剂阻断;以及c)它可能具有与Ptox诱导的泵通道相似的特性。

项目成果

期刊论文数量(0)
专著数量(0)
科研奖励数量(0)
会议论文数量(0)
专利数量(0)

数据更新时间:{{ journalArticles.updateTime }}

{{ item.title }}
{{ item.translation_title }}
  • DOI:
    {{ item.doi }}
  • 发表时间:
    {{ item.publish_year }}
  • 期刊:
  • 影响因子:
    {{ item.factor }}
  • 作者:
    {{ item.authors }}
  • 通讯作者:
    {{ item.author }}

数据更新时间:{{ journalArticles.updateTime }}

{{ item.title }}
  • 作者:
    {{ item.author }}

数据更新时间:{{ monograph.updateTime }}

{{ item.title }}
  • 作者:
    {{ item.author }}

数据更新时间:{{ sciAawards.updateTime }}

{{ item.title }}
  • 作者:
    {{ item.author }}

数据更新时间:{{ conferencePapers.updateTime }}

{{ item.title }}
  • 作者:
    {{ item.author }}

数据更新时间:{{ patent.updateTime }}

Andrew, Robert其他文献

Andrew, Robert的其他文献

{{ item.title }}
{{ item.translation_title }}
  • DOI:
    {{ item.doi }}
  • 发表时间:
    {{ item.publish_year }}
  • 期刊:
  • 影响因子:
    {{ item.factor }}
  • 作者:
    {{ item.authors }}
  • 通讯作者:
    {{ item.author }}

{{ truncateString('Andrew, Robert', 18)}}的其他基金

Converting the sodium-potassium pump into a shutdown channel
将钠钾泵转变为关闭通道
  • 批准号:
    RGPIN-2017-04624
  • 财政年份:
    2021
  • 资助金额:
    $ 1.89万
  • 项目类别:
    Discovery Grants Program - Individual
Converting the sodium-potassium pump into a shutdown channel
将钠钾泵转变为关闭通道
  • 批准号:
    RGPIN-2017-04624
  • 财政年份:
    2020
  • 资助金额:
    $ 1.89万
  • 项目类别:
    Discovery Grants Program - Individual
Converting the sodium-potassium pump into a shutdown channel
将钠钾泵转变为关闭通道
  • 批准号:
    RGPIN-2017-04624
  • 财政年份:
    2019
  • 资助金额:
    $ 1.89万
  • 项目类别:
    Discovery Grants Program - Individual
Converting the sodium-potassium pump into a shutdown channel
将钠钾泵转变为关闭通道
  • 批准号:
    RGPIN-2017-04624
  • 财政年份:
    2018
  • 资助金额:
    $ 1.89万
  • 项目类别:
    Discovery Grants Program - Individual
Converting the sodium-potassium pump into a shutdown channel
将钠钾泵转变为关闭通道
  • 批准号:
    RGPIN-2017-04624
  • 财政年份:
    2017
  • 资助金额:
    $ 1.89万
  • 项目类别:
    Discovery Grants Program - Individual

相似国自然基金

上皮钠离子通道(ENaC)在血管内皮的功能和作用
  • 批准号:
    81170236
  • 批准年份:
    2011
  • 资助金额:
    60.0 万元
  • 项目类别:
    面上项目
循环二氧化碳水平升高导致延迟钠电流增加的致心律失常作用及其发生机制的研究
  • 批准号:
    81170156
  • 批准年份:
    2011
  • 资助金额:
    60.0 万元
  • 项目类别:
    面上项目
亚硝酸钠对肝移植物缺血再灌注损伤的保护作用及其机制
  • 批准号:
    81170416
  • 批准年份:
    2011
  • 资助金额:
    60.0 万元
  • 项目类别:
    面上项目
中枢钠氢交换蛋白3在睡眠呼吸暂停呼吸控制稳定性中的作用和调控机制
  • 批准号:
    30900646
  • 批准年份:
    2009
  • 资助金额:
    20.0 万元
  • 项目类别:
    青年科学基金项目

相似海外基金

Uncovering the Functional Effects of Neurotrophins in the Auditory Brainstem
揭示神经营养素对听觉脑干的功能影响
  • 批准号:
    10823506
  • 财政年份:
    2024
  • 资助金额:
    $ 1.89万
  • 项目类别:
Salt Mediated Cross Talk Between Lymphatic Vessels and Immune Cells in Kidney Disease
盐介导肾脏疾病中淋巴管和免疫细胞之间的交互作用
  • 批准号:
    10636755
  • 财政年份:
    2023
  • 资助金额:
    $ 1.89万
  • 项目类别:
Distinct Ion Channel Pools and Intercalated Disk Nanoscale Structure Regulate Cardiac Conduction
独特的离子通道池和闰盘纳米级结构调节心脏传导
  • 批准号:
    10676368
  • 财政年份:
    2023
  • 资助金额:
    $ 1.89万
  • 项目类别:
Retinal Circuitry Response to Nerve Injury
视网膜回路对神经损伤的反应
  • 批准号:
    10751621
  • 财政年份:
    2023
  • 资助金额:
    $ 1.89万
  • 项目类别:
Preclinical validation of Kir4.1/5.1 inhibitors for overcoming diuretic resistance
Kir4.1/5.1 抑制剂克服利尿剂抵抗的临床前验证
  • 批准号:
    10740429
  • 财政年份:
    2023
  • 资助金额:
    $ 1.89万
  • 项目类别:
Chemical biology of voltage-gated cation channels
电压门控阳离子通道的化学生物学
  • 批准号:
    10552311
  • 财政年份:
    2023
  • 资助金额:
    $ 1.89万
  • 项目类别:
Architecture, dynamics and regulation of erythrocyte ankyrin-1 complexes
红细胞ankyrin-1复合物的结构、动力学和调节
  • 批准号:
    10638440
  • 财政年份:
    2023
  • 资助金额:
    $ 1.89万
  • 项目类别:
The role of the COP9 signalosome in distal nephron remodeling
COP9信号体在远端肾单位重塑中的作用
  • 批准号:
    10723624
  • 财政年份:
    2023
  • 资助金额:
    $ 1.89万
  • 项目类别:
Lymphocyte Antigen 6 (Ly6) Proteins: New Players in Chronic Pain
淋巴细胞抗原 6 (Ly6) 蛋白:慢性疼痛的新参与者
  • 批准号:
    10784019
  • 财政年份:
    2023
  • 资助金额:
    $ 1.89万
  • 项目类别:
miR-137 Regulation of Intrinsic Excitability
miR-137 内在兴奋性的调节
  • 批准号:
    10719579
  • 财政年份:
    2023
  • 资助金额:
    $ 1.89万
  • 项目类别:
{{ showInfoDetail.title }}

作者:{{ showInfoDetail.author }}

知道了