Reduced presynaptic dopamine activity in fibromyalgia syndrome demonstrated with positron emission tomography: a pilot study.
Patrick B. Wood, James C. Patterson II, John J. Sunderland, Kerrie H. Tainter, Michael Fl. Glabus, and David L. Lilien.

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-[18F]fluoro-L-DOPA as a tracer. Semiquantitative analysis revealed reductions in 6-[18F]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.

The Journal of Pain, Vol 8, No 1 (January), 2007: pp 51-58.