Article

Reduced Presynaptic Dopamine Activity in Fibromyalgia Syndrome Demonstrated With Positron Emission Tomography: A Pilot Study

Department of Family Medicine and Anesthesiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA 71103, USA.
Journal of Pain (Impact Factor: 4.01). 02/2007; 8(1):51-8. DOI: 10.1016/j.jpain.2006.05.014
Source: PubMed

ABSTRACT

Although the pathophysiology underlying the pain of fibromyalgia syndrome (FMS) remains unknown, a variety of clinical and investigational findings suggests a dysregulation of dopaminergic neurotransmission. We therefore investigated presynaptic dopaminergic function in 6 female FMS patients in comparison to 8 age- and gender-matched controls as assessed by positron emission tomography with 6-[(18)F]fluoro-L-DOPA as a tracer. Semiquantitative analysis revealed reductions in 6-[(18)F]fluoro-L-DOPA uptake in several brain regions, indicating a disruption of presynaptic dopamine activity wherein dopamine plays a putative role in natural analgesia. Although the small sample size makes these findings preliminary, it appears that FMS might be characterized by a disruption of dopaminergic neurotransmission. PERSPECTIVE: An association between FMS and reduced dopamine metabolism within the pain neuromatrix provides important insights into the pathophysiology of this mysterious disorder.

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Available from: John Sunderland, Sep 09, 2014
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    • "Recent studies suggest that the alterations or dysfunctions of the mesolimbic reward pathway contribute to the pathology of chronic pain (Farmer et al., 2012, Navratilova andPorreca, 2014). For example, in an imaging study, self-reported pain induced by hypertonic saline injection in healthy volunteers correlated with the amount of dopamine released in basal ganglia implicating dopamine activity in endogenous analgesia (Wood et al., 2007a, Wood et al., 2007b). In contrast to healthy subjects, patients with fibromyalgia did not show dopamine release in response to noxious stimulation (Wood et al., 2007a). "
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    ABSTRACT: Chronic pain is an important public health problem that negatively impacts quality of life of affected individuals and exacts enormous socio-economic costs. Chronic pain is often accompanied by comorbid emotional disorders including anxiety, depression and possibly anhedonia. The neural circuits underlying the intersection of pain and pleasure are not well understood. We summarize recent human and animal investigations demonstrating that aversive aspects of pain are encoded in brain regions overlapping with areas processing reward and motivation. We highlight findings revealing anatomical and functional alterations of reward/motivation circuits in chronic pain. Finally, we review supporting evidence for the concept that pain relief is rewarding and activates brain reward/motivation circuits. Adaptations in brain reward circuits may be fundamental to the pathology of chronic pain. Knowledge of brain reward processing in the context of pain could lead to the development of new therapeutics for the treatment of emotional aspects of pain and comorbid conditions. This article is protected by copyright. All rights reserved.
    Full-text · Article · Jan 2016 · The Journal of Comparative Neurology
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    • "In contrast, in patients with schizophrenia, an insensitivity to pain has been documented early [10] and confirmed in more recent experimental studies [11], [12]. Further evidence for a dopaminergic influence on pain perception derives from observations of altered dopaminergic neurotransmission in various chronic pain conditions [13]–[16]. In addition, small clinical studies indicated that dopaminergic agents can relieve chronic pain [17]–[19]. "
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    ABSTRACT: Pain is a multidimensional experience, which includes sensory, cognitive, and affective aspects. Converging lines of evidence indicate that dopaminergic neurotransmission plays an important role in human pain perception. However, the precise effects of dopamine on different aspects of pain perception remain to be elucidated. To address this question, we experimentally decreased dopaminergic neurotransmission in 22 healthy human subjects using Acute Phenylalanine and Tyrosine Depletion (APTD). During APTD and a control condition we applied brief painful laser stimuli to the hand, assessed different aspects of pain perception, and recorded electroencephalographic responses. APTD-induced decreases of cerebral dopaminergic activity did not influence sensory aspects of pain perception. In contrast, APTD yielded increases of pain unpleasantness. The increases of unpleasantness ratings positively correlated with effectiveness of APTD. Our finding of an influence of dopaminergic neurotransmission on affective but not sensory aspects of phasic pain suggests that analgesic effects of dopamine might be mediated by indirect effects on pain affect rather than by direct effects on ascending nociceptive signals. These findings contribute to our understanding of the complex relationship between dopamine and pain perception, which may play a role in various clinical pain states.
    Full-text · Article · Apr 2014 · PLoS ONE
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    • "FM patients have been shown to present structural differences in the brain [14] [20]. Furthermore, there are several evidences of central sensitization at various levels in the nervous system [12], as well as neurochemical imbalances in the central nervous system leading to a central amplification of pain perception [15] [46]. "
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