Neurobiol Dis 2002 Dec;11(3):434-42
Schwarz MJ, Offenbaecher M, Neumeister A, Ewert T, Willeit M, Praschak-Rieder N, Zach J, Zacherl M, Lossau K, Weisser R, Stucki G, Ackenheil M.
Psychiatric Hospital, University of Munich, D-80336, Munich, Germany
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Fibromyalgia (FM) is a prevalent syndrome with chronic pain and a hypothesized underlying disturbance of the tryptophan (TRP) metabolism. We performed a tryptophan depletion (TD) test in 17 FM patients and 17 controls.
TRP, 5-hydroxyindoleacetic acid (5-HIAA), kynurenine (KYN), and interleukin-6 (IL-6) were measured. Additionally pain perception was monitored in the FM patients. FM patients and controls exhibited a decrease of TRP and KYN during TD. 5-HIAA levels also decreased in all controls and in 11 FM patients, but showed a marked increase in 6 FM patients. IL-6 significantly increased during TD in the patients, but not in the controls.
Pain perception was not affected in the FM patients. These data demonstrate an altered TRP metabolism in a subgroup of FM patients, where the TD seems to activate 5-HT metabolism. Our findings may have diagnostic as well as therapeutic implications in the field of fibromyalgia.
PMID: 12586552 [PubMed – in process]