Supraspinal Modulation of Nociceptive Reactions in Fibromyalgia

描述（申请人提供）：纤维肌痛综合征（FMS）是一种潜伏性疾病，导致70%的患者残疾，并造成工作和生产力的巨大损失。据估计，美国有800万至1200万成年人受到FMS的影响，使其成为最常见的慢性广泛性疼痛综合征。导致纤维肌痛的发展和维持的确切机制尚不清楚。但是，越来越多的证据表明，中枢神经系统（CNS）的异常伤害性加工可能是由于脊髓上调制的异常。我们的实验室已经开发了程序来评估生理和主观伤害性反应（伤害性屈曲反射，皮肤电导，心率，疼痛报告）的脊髓上调制。一个标准化的图片观看范例被用来实验操纵情绪效价（不愉快，中性，愉快），和生理情绪操纵检查验证情绪反应。在观看图片期间，递送有害电刺激（在图片效价上平衡）并且记录伤害性反应并通过图片效价进行平均。在健康对照组中，我们已经表明，伤害性反应是可靠的调制平行的图片效价。不愉快的图片促进伤害性反应，愉快的图片抑制伤害性反应（这种效应解释了反应中47-52%的组合方差）。由于伤害性屈曲反射（一种脊髓反射）受到调制，这表明下行调制回路参与其中。因此，这些程序提供了一个非侵入性的方式来研究脊髓上调制。本研究将使用图片观看范例来研究FMS患者、类风湿性关节炎（RA）患者和无疼痛对照组的脊髓上调制。类风湿关节炎患者提供了重要的控制慢性疼痛史和其他共病变量（如，心理困扰，健康/身体功能，适应不良的应对），可能会影响情绪-疼痛的关系。此外，情绪因素在RA和FMS疼痛中也很重要，但目前尚不清楚情绪在这两种情况下是否起着同样有效的作用。此外，虽然RA也与痛觉过敏相关，但RA脊髓上调节功能障碍的人类证据有限。本研究的具体目的是：（1）检查FMS患者伤害性反应的脊髓上调制和（2）评估FMS和RA患者的痛觉过敏。

DESCRIPTION (provided by applicant): Fibromyalgia syndrome (FMS) is an insidious disease that results in disability for 70% of those who suffer from it and tremendous loss of work and productivity. It is estimated that 8-12 million adults in the U.S. are affected by FMS, making it the most common chronic widespread pain syndrome. The exact mechanisms leading to the development and maintenance of fibromyalgia are unknown. But, accumulating evidence suggests abnormal nociceptive processing in the central nervous system (CNS) that could result from aberrations in supraspinal modulation. Our laboratory has developed procedures to assess supraspinal modulation of physiological and subjective nociceptive reactions (nociceptive flexion reflex, skin conductance, heart rate, pain report). A standardized picture-viewing paradigm is used to experimentally manipulate emotional valence (unpleasant, neutral, pleasant), and physiological-emotional manipulation checks verify emotional reactions. During picture-viewing, noxious electric stimuli are delivered (balanced across picture valence) and nociceptive reactions are recorded and averaged by picture valence. In healthy controls, we have shown that nociceptive reactions are reliably modulated in parallel by picture valence. Unpleasant pictures facilitate nociceptive reactions and pleasant pictures inhibit nociceptive reactions (an effect that explains 47-52% of the combined variance in the reactions). Because the nociceptive flexion reflex (a spinal reflex) is modulated, this suggests descending modulatory circuits are involved. Therefore, these procedures provide a non-invasive way to study supraspinal modulation. The present study will use the picture-viewing paradigm to study supraspinal modulation in FMS patients, rheumatoid arthritis (RA) patients, and no-pain controls. RA patients provide important controls for chronic pain history and other comorbid variables (eg, psychological distress, health/physical functioning, maladaptive coping) that could influence the emotion-pain relationship. Also, emotional factors are important in RA and FMS pain, but it is unclear whether emotion plays an equally potent role in both conditions. Further, there is limited human evidence for dysfunctional supraspinal modulation in RA, although RA is also associated with hyperalgesia. The specific aims of this study are: (1) To examine supraspinal modulation of nociceptive reactions in FMS patients and (2) To assess for hyperalgesia in FMS and RA patients.