Supraspinal Modulation of Nociceptive Reactions in Fibromyalgia

描述（由申请人提供）：纤维肌痛综合征（FMS）是一种隐蔽性疾病，70%的患者会因此而丧失工作能力和生产力。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）的伤害性加工异常可能是由椎上调节的异常引起的。我们的实验室已经开发了评估生理和主观伤害反应（伤害性屈曲反射，皮肤电导，心率，疼痛报告）的椎管上调节的程序。标准化的图片观看范式被用来实验性地操纵情绪效价（不愉快、中性、愉快），生理-情绪操纵检查验证情绪反应。在观看图片的过程中，传递有害的电刺激（在图片效价上平衡），并记录伤害性反应并按图片效价平均。在健康对照中，我们已经证明伤害性反应可靠地由图像效价平行调节。不愉快的图片促进了伤害性反应，而愉快的图片抑制了伤害性反应（这一效应解释了47-52%的反应总方差）。因为伤害性屈曲反射（一种脊柱反射）是被调节的，这表明下行调节回路参与其中。因此，这些手术提供了一种非侵入性的方法来研究椎管上调节。本研究将使用图片观看范式来研究FMS患者、类风湿关节炎（RA）患者和无疼痛对照患者的椎上调节。类风湿性关节炎患者对慢性疼痛史和其他可能影响情绪-疼痛关系的共病变量（如心理困扰、健康/身体功能、适应不良应对）提供了重要的控制。此外，情绪因素在类风湿性关节炎和FMS疼痛中也很重要，但尚不清楚情绪在这两种情况下是否同样有效。此外，尽管类风湿关节炎也与痛觉过敏有关，但关于类风湿关节炎椎上调节功能失调的人类证据有限。本研究的具体目的是：(1)研究FMS患者痛觉反应的椎上调节；(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.