title: Increased interstitial concentrations of pyruvate and lactate in the trapezius muscle of patients with fibromyalgia: a microdialysis study.
abstract: OBJECTIVE
  The aim of this study was to compare the interstitial concentrations of pyruvate, lactate and glutamate in the trapezius muscle between patients with fibromyalgia syndrome and healthy controls.
  
  
  METHODS
  Comparative cross-sectional study.
  
  
  METHODS
  Patients with fibromyalgia (n = 19) and healthy controls (n = 19); all women.
  
  
  METHODS
  Subjects answered a questionnaire about different aspects of pain. Pressure pain thresholds over the trapezius and tibialis anterior muscles were determined. The inter-stitial concentrations of pyruvate, lactate and glutamate were determined in the resting trapezius muscle by the microdialysis technique, with samples collected every hour for 5 consecutive hours. Pain intensity was also rated.
  
  
  RESULTS
  Significantly higher interstitial concentrations of pyruvate and lactate were found in patients with fibromyalgia- syndrome. The multivariate regression analyses of group membership and pressure pain thresholds of the trapezius confirmed the importance of pyruvate and lactate.
  
  
  CONCLUSIONS
  Different mechanisms that may increase pyruvate and lactate in patients with fibromyalgia syndrome are discussed. Improved understanding of peripheral muscle alterations in patients with fibromyalgia syndrome could lead to mechanism-based rehabilitation.
authors.affiliation: Rehabilitation Medicine, Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden. Bjorn.Gerdle@liu.se
authors.forename: Björn
authors.initials: B
authors.lastname: Gerdle
authors.forename: Kristina
authors.initials: K
authors.lastname: Söderberg
authors.forename: Laia
authors.initials: L
authors.lastname: Salvador Puigvert
authors.forename: Lars
authors.initials: L
authors.lastname: Rosendal
authors.forename: Britt
authors.initials: B
authors.lastname: Larsson
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D045604:Extracellular Fluid / Q000737:chemistry; D005260:Female; D005356:Fibromyalgia / Q000378:metabolism* / Q000534:rehabilitation; D018698:Glutamic Acid / Q000032:analysis* / Q000378:metabolism; D006801:Humans; D019344:Lactic Acid / Q000032:analysis* / Q000378:metabolism; D017551:Microdialysis; D018482:Muscle, Skeletal / Q000378:metabolism*; D010147:Pain Measurement; D019289:Pyruvic Acid / Q000032:analysis* / Q000378:metabolism; D011795:Surveys and Questionnaires
chemical_list: D019344:Lactic Acid; D018698:Glutamic Acid; D019289:Pyruvic Acid