title: Oxidative capacity and fatigability in run-trained malignant hyperthermia-susceptible mice.
abstract: BACKGROUND
  The purpose of this study was to test the hypothesis that malignant hyperthermia model mice (RyR1Y522S/wt) are more vulnerable to exercise-induced muscle injury and fatigability and adapt less to run training.
  
  
  METHODS
  After 6 weeks of voluntary wheel running, we measured anterior crural muscle fatigability, muscle injury, and cytochrome oxidase (COX) and citrate synthase (CS).
  
  
  RESULTS
  Although RyR1Y522S/wt mice ran without undergoing MH episodes, they ran 42% less distance than wild-type (WT) mice. Muscles from WT mice exhibited increased fatigue resistance and COX content after training. Muscles from RyR1Y522S/wt mice demonstrated no significant change in fatigability or COX and CS after training. However, muscles from RyR1Y522S/wt mice displayed less intrinsic fatigability and greater COX/CS content and muscle damage than WT mice.
  
  
  CONCLUSIONS
  RyR1Y522S/wt mice can run without having rhabdomyolysis, and their inability to adapt to training appears to stem from intrinsic enhancement of mitochondrial enzymes and fatigue resistance.
authors.affiliation: Muscle Biology Laboratory, Department of Kinesiology and Health, Georgia State University, P.O. Box 3975, Atlanta, Georgia 30302-3975, USA.
authors.forename: Clement
authors.initials: C
authors.lastname: Rouviere
authors.forename: Benjamin T
authors.initials: BT
authors.lastname: Corona
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Ingalls
mesh_terms: D000332:Aerobiosis; D000818:Animals; D015153:Blotting, Western; D002950:Citrate (si)-Synthase / Q000378:metabolism; D004198:Disease Susceptibility; D003576:Electron Transport Complex IV / Q000378:metabolism; D005260:Female; D006974:Hypertension, Malignant / Q000378:metabolism* / Q000503:physiopathology*; D007537:Isometric Contraction / Q000502:physiology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008931:Mitochondria, Muscle / Q000378:metabolism; D018763:Muscle Fatigue / Q000502:physiology*; D018485:Muscle Fibers, Skeletal / Q000473:pathology; D053580:Muscle Strength / Q000502:physiology; D018482:Muscle, Skeletal / Q000473:pathology* / Q000503:physiopathology*; D018995:Myosin Heavy Chains / Q000378:metabolism; D009929:Organ Size / Q000502:physiology; D010084:Oxidation-Reduction; D010805:Physical Conditioning, Animal / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology; D016133:Polymerase Chain Reaction; D012420:Running / Q000502:physiology; D019837:Ryanodine Receptor Calcium Release Channel / Q000235:genetics
chemical_list: D019837:Ryanodine Receptor Calcium Release Channel; D003576:Electron Transport Complex IV; D002950:Citrate (si)-Synthase; D018995:Myosin Heavy Chains