title: P-31 magnetic resonance spectroscopy in polymyositis and dermatomyositis. Altered energy utilization during exercise.
abstract: OBJECTIVE
  To explore alterations in energy utilization as a potential etiology for weakness in polymyositis and dermatomyositis (PM/DM).
  
  
  METHODS
  P-31 magnetic resonance spectroscopy studies were performed in patients with acute and treated PM/DM and in normal controls, at rest and with exercise.
  
  
  RESULTS
  Patients with acute and treated PM/DM showed increased ratios of inorganic phosphate to phosphocreatine (PCr) during exercise, with loss of ATP disproportional to loss of PCr.
  
  
  CONCLUSIONS
  This study demonstrates changes in energy utilization in PM/DM, thus supporting the notion of a metabolic etiology for the weakness associated with these diseases.
authors.affiliation: Department of Rheumatology, Geisinger Medical Center, Danville, Pennsylvania 17822.
authors.forename: E D
authors.initials: ED
authors.lastname: Newman
authors.forename: R J
authors.initials: RJ
authors.lastname: Kurland
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D003882:Dermatomyositis / Q000378:metabolism*; D004734:Energy Metabolism / Q000502:physiology*; D015444:Exercise / Q000502:physiology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D009132:Muscles / Q000378:metabolism; D009220:Myositis / Q000378:metabolism*; D010710:Phosphates / Q000378:metabolism; D010725:Phosphocreatine / Q000378:metabolism; D010758:Phosphorus
chemical_list: D010710:Phosphates; D010725:Phosphocreatine; D010758:Phosphorus; D000255:Adenosine Triphosphate