Regulation of spinal NK1R expression by chronic stress

慢性应激对脊髓 NK1R 表达的调节

• 批准号: 7140224
• 负责人: SYLVIE BRADESI
• 金额: $ 15.38万
• 依托单位: BRENTWOOD BIOMEDICAL RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-22 至 2009-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7140224
• 关键词: afferent nerve; biological signal transduction; cAMP response element binding protein; central neural pathway /tract; dorsal horn; enteric nervous system; gel mobility shift assay; gene expression; gene targeting; hyperalgesia; immunocytochemistry; irritable bowel syndrome; laboratory rat; microglia; neuroimmunomodulation; nociceptors; nuclear factor kappa beta; pain; pathologic process; pharmacology; psychological stressor; receptor expression; spinal cord; stress; western blottings

DESCRIPTION (provided by applicant): Converging evidence supports a correlation between sustained stress and the onset or exacerbation of symptoms for Irritable Bowel Syndrome. Some studies indicate a correlation between intense stress and persistent alteration of visceral sensitivity. A better understanding of the mechanisms by which stress can lead to sustained visceral hyperalgesia may have important implications for therapeutic approach of functional bowel disorders. We previously showed that chronic psychological stress in rat leads to sustained increase of visceral nociception that involves NK1 receptors (NK1R) activation in the spinal cord. The current proposal is based on the general hypothesis that spinal up-regulation of NK1Rs observed in this model is mediated by the interplay of peripheral immune activation and increased signaling to spinal dorsal horn (DH) neurons via primary afferent fibers, spinal microglia and descending spinal pathways. We will focus on the role of signaling molecules derived from primary afferent fibers in the regulation of NK1R gene expression in spinal DH neurons. We will use a combination of quantitative real time PCR, immunohistochemistry, electrophoretic mobility shift assay, Western blot and in vivo pharmacological approach to identify the mediators involved in this regulation. In aim 1, we will evaluate the time course correlation between stress-induced colonic immune activation, primary afferent fibers stimulation and subsequent increase of NK1Rexpression in DH neurons. In aim 2, we will address the potential correlation between stress-induced up-regulation of spinal NK1R and activation of the transcription factors CREB and NFkappaB in the same neurons. In aim 3, we will evaluate, through pharmacological treatment, the functional contribution of primary afferent neurons in stress-induced activation of CREB and NFkappaB, and increased expression of NK1R. The specific role of CGRP and spinal TNFalpha in this modulatory effect will be assessed. This proposal is expected to provide new insights into the mechanisms by which stress affects the processing of visceral nociception.

描述（由申请人提供）：汇聚的证据支持持续压力与肠易激综合征症状的发作或加重之间的相关性。一些研究表明，强烈的压力和内脏敏感性的持续变化之间存在相关性。 更好地理解应激导致持续内脏痛觉过敏的机制可能对功能性肠病的治疗方法具有重要意义。我们以前的研究表明，大鼠慢性心理应激导致内脏伤害性感受持续增加，这涉及脊髓中的NK1受体（NK1R）激活。目前的建议是基于这样的一般假设，即在该模型中观察到的NK1Rs的脊髓上调是由外周免疫激活和通过初级传入纤维、脊髓小胶质细胞和下行脊髓通路向脊髓背角（DH）神经元的信号传导增加的相互作用介导的。我们将集中在来自初级传入纤维的信号分子在脊髓DH神经元的NK1R基因表达的调节中的作用。我们将使用定量真实的时间PCR，免疫组织化学，电泳迁移率变动分析，蛋白质印迹和体内药理学方法的组合，以确定参与这种调节的介质。在目的1中，我们将评估应激诱导的结肠免疫激活、初级传入纤维刺激和随后的DH神经元中NK1R表达增加之间的时间过程相关性。在目标2中，我们将解决应激诱导的脊髓NK1R上调与相同神经元中转录因子CREB和NF κ B激活之间的潜在相关性。在目标3中，我们将通过药物治疗评估初级传入神经元在应激诱导的CREB和NF κ B激活以及NK1R表达增加中的功能贡献。将评估CGRP和脊髓TNF α在这种调节作用中的具体作用。这一建议有望为应激影响内脏伤害感受的机制提供新的见解。