Amygdala mechanisms of pain aversion

杏仁核的疼痛厌恶机制

基本信息

批准号：
10163274
负责人：
Gregory Scherrer
金额：
$ 30.34万
依托单位：
UNIV OF NORTH CAROLINA CHAPEL HILL
依托单位国家：
美国
项目类别：
财政年份：
2018
资助国家：
美国
起止时间：
2018-04-15 至 2023-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10163274
关键词：
Acute Acute Pain Address Affect Affective American Amygdaloid structure Anterior Anxiety Behavior Brain Brain Stem Brain region Calcium Calcium Spikes Cell Nucleus Cells Code Data Dependovirus Desire for food Detection Development Disease Electrophysiology (science)Emotional Enterobacteria phage P1 Cre recombinase Female Fluorescent in Situ Hybridization Fostering Fright Functional disorder Future Image In Situ Hybridization Intralaminar Nuclear Group Knowledge Lead Learning Light Mental Depression Mental disorders Methods Mission Motivation Mus National Institute of Neurological Disorders and Stroke Negative Valence Neurobiology Neurons Nociception Output Pain Pain Research Pain quality Pathologic Pattern Personal Satisfaction Play Process Public Health Research Role Sensory Shapes Signal Transduction Slice Spinal Cord Stimulus Structure Sucrose Synapses Synaptic Transmission System Testing Thalamic structure Touch sensation United States National Institutes of Health Viral Water Withdrawal base cell type chronic neuropathic pain chronic pain chronic pain patient comorbidity experience experimental study innovation male microendoscopy nerve injury neurotransmission novel novel strategies novel therapeutic intervention optogenetics presynaptic neurons prevent rabies viral tracing relating to nervous system somatosensory tool

项目摘要

Pain is a multidimensional experience with sensory and affective components. The aversive quality of pain (i.e. pain aversion/unpleasantness) causes the majority of chronic pain patients' suffering, and often results in comorbid disorders (anxiety/depression). However, the mechanisms by which our brain assigns a negative emotional valence to nociceptive information to generate pain aversion remain unresolved. This gap in knowledge prevents targeting pain aversion mechanisms to restore the wellbeing of chronic pain patients. Nociceptive information only acquires its aversive quality once processed through emotional valence circuits. Several cortical and limbic structures contribute to this process, including the anterior cingulate/prefrontal/insular cortices, and the amygdala. We obtained preliminary data in mice suggesting that pain aversion is encoded in neural activity patterns in the basolateral amygdala (BLA). First, we found that BLA activity patterns evolve during chronic neuropathic pain, so that innocuous stimuli such as light touch and cold aberrantly engage BLA nociceptive neural ensembles. This result suggests that the BLA miscodes somatosensory information, possibly explaining how these innocuous stimuli become painful (i.e. aversive) during chronic pain. Second, inhibition of tagged nociceptive BLA neurons with chemogenetics did not alter paw withdrawal from noxious stimuli, but nearly eliminated pain affective-motivational behaviors and avoidance of noxious stimuli. This finding suggests that painful stimuli are detected, but are no longer perceived as aversive. Building on these preliminary data, we propose to elucidate the mechanisms that shape pain aversion in the BLA. Fluorescent microendoscopy of calcium dynamics in freely moving mice experiencing pain will determine how noxious stimuli are encoded in BLA valence neural ensembles, acutely and during chronic pain (Aim 1). Viral tracing and chemogenetic/optogenetic inhibition of specific BLA neuron inputs will uncover the circuits that generate pain aversion (Aim 2). Finally, multilabeling in situ hybridization and slice electrophysiology studies will identify the transmitters and synaptic mechanisms that regulate activity of BLA neurons, and the pathological alterations associated with the emergence of chronic pain (Aim 3). This research will transform our understanding of pain neurobiology by dissecting the mechanisms underlying pain affect and, in the long-term, will uncover new approaches to treat chronic pain by weakening the associated aversion and preventing comorbid psychological disorders, such as anxiety and depression.

疼痛是一种包含感觉和情感成分的多维体验。疼痛的厌恶性质（即疼痛厌恶/不愉快）导致大多数慢性疼痛患者的痛苦，并经常导致共病（焦虑/抑郁）。然而，我们的大脑分配负面信息的机制产生疼痛厌恶的伤害性信息的情绪效价仍未解决。这个差距在知识阻碍了针对疼痛厌恶机制来恢复慢性疼痛患者的健康。伤害性信息只有在经过情绪效价回路处理后才会获得其厌恶的性质。几种皮质和边缘结构有助于这一过程，包括前扣带皮层/前额叶/岛叶皮质和杏仁核。我们在小鼠身上获得的初步数据表明，疼痛厌恶是在基底外侧杏仁核（BLA）的神经活动模式中编码的。首先，我们发现 BLA 活动模式在慢性神经病理性疼痛期间演变，因此轻触和寒冷等无害刺激会异常地参与 BLA 伤害性神经系统。这一结果表明 BLA 错误编码了体感信息，这可能解释了这些无害的刺激如何在慢性疼痛期间变得痛苦（即厌恶）。其次，用化学遗传学抑制标记的伤害性 BLA 神经元并不会改变爪子对有害刺激的退缩，但几乎消除了疼痛情感动机行为和对有害刺激的回避。这一发现表明，痛苦的刺激被检测到，但不再被视为令人厌恶。基于这些初步数据，我们建议阐明 BLA 中形成疼痛厌恶的机制。对经历疼痛的自由活动小鼠的钙动态进行荧光显微内窥镜检查，将确定急性疼痛和慢性疼痛期间 BLA 价神经元中有害刺激的编码方式（目标 1）。病毒追踪和特定 BLA 神经元输入的化学遗传学/光遗传学抑制将揭示产生疼痛厌恶的回路（目标 2）。最后，多标记原位杂交和切片电生理学研究将确定调节 BLA 神经元活动的递质和突触机制，以及与慢性疼痛出现相关的病理改变（目标 3）。这项研究将通过剖析疼痛影响的机制来改变我们对疼痛神经生物学的理解，从长远来看，将通过削弱相关的厌恶感和预防焦虑和抑郁等共病心理障碍来发现治疗慢性疼痛的新方法。