Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0016053 (fibromyalgia)
 4,687 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Characteristic symptoms of fibromyalgia syndrome (FM) include widespread pain, fatigue, sleep abnormalities, and distress. FM patients show psychophysical evidence for mechanical, thermal, and electrical hyperalgesia. To fulfill FM criteria, the mechanical hyperalgesia needs to be widespread and present in at least 11 out of 18 well-defined body areas (tender points). Peripheral and central abnormalities of nociception have been described in FM and these changes may be relevant for the increased pain experienced by these patients. Important nociceptor systems in the skin and muscle seem to undergo profound changes in FM patients by yet unknown mechanisms. These changes may result from the release of algesic substances after muscle or other soft tissue injury. These pain mediators can sensitize important nociceptor systems, including the transient receptor potential channel, vanilloid subfamily member 1 (TRPV1), acid sensing ion channel (ASIC) receptors, and purino-receptors (P2X3). Subsequently, tissue mediators of inflammation and nerve growth factors can excite these receptors and cause substantial changes in pain sensitivity. FM pain is widespread and does not seem to be restricted to tender points (TP). It frequently comprises multiple areas of deep tissue pain (trigger points) with adjacent much larger areas of referred pain. Analgesia of areas of extensive nociceptive input has been found to provide often long lasting local as well as general pain relief. Thus interventions aimed at reducing local FM pain seem to be effective but need to focus less on tender points but more on trigger points (TrP) and other body areas of heightened pain and inflammation.
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PMID:Are tender point injections beneficial: the role of tonic nociception in fibromyalgia. 1645 21

In women, clinical studies suggest that functional pain syndromes such as irritable bowel syndrome, interstitial cystitis, and fibromyalgia, are co-morbid with endometriosis, chronic pelvic pain, and others diseases. One of the possible explanations for this phenomenon is visceral cross-sensitization in which increased nociceptive input from inflamed reproductive system organs sensitize neurons that receive convergent input from an unaffected visceral organ to the same dorsal root ganglion (DRG). The purpose of this study was to determine whether primary sensory neurons that innervate both visceral organs--the uterus and the colon--express nociceptive ATP-sensitive purinergic (P2X3) and capsaicin-sensitive vanilloid (TRPV1) receptors. To test this hypothesis, cell bodies of colonic and uterine DRG were retrogradely labeled with fluorescent tracer dyes micro-injected into the colon/rectum and uterus of rats. Ganglia were harvested, cryo-protected, and cut in 20-microm slices for fluorescent microscopy to identify positively stained cells. Up to 5% neurons were colon-specific or uterus-specific, and 10%-15% of labeled DRG neurons innervate both viscera in the lumbosacral neurons (L1-S3 levels). We found that viscerally labeled DRGs express nociceptive P2X3 and TRPV1 receptors. Our results suggest a novel form of visceral sensory integration in the DRG that may underlie co-morbidity of many functional pain syndromes.
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PMID:Visceral sensory neurons that innervate both uterus and colon express nociceptive TRPv1 and P2X3 receptors in rats. 1864 15