Power output of fast and slow skeletal muscles of mdx (dystrophic) and control mice after clenbuterol treatment.
The mdx mouse is the most commonly used animal model for Duchenne muscular dystrophy. We tested the null hypothesis that 20 weeks of clenbuterol treatment ( approximately 2 mg kg-1 day-1) of mdx and control mice would have no effect on the absolute and specific force (Po, kN m-2) and absolute and normalised power output (W kg-1) of extensor digitorum longus (EDL) and soleus muscles. For mdx and control mice, clenbuterol treatment produced modest increases in the mass of the two muscles but did not increase absolute or specific force or normalised power output. For absolute power output, only the EDL muscles of mdx mice showed a difference following treatment, with the power output of treated mice being 118 % that of the untreated mice. The modest effects of clenbuterol treatment on the dynamic properties of skeletal muscle provide little support for any improvement in muscle function for the dystrophic condition.
Lynch
G S
GS
Institute of Gerontology and Departments of Physiology and Biomedical Engineering, The University of Michigan, Ann Arbor, MI 48109-2007, USA. g.lynch@physiology.unimelb.edu.au
Hinkle
R T
RT
Faulkner
J A
JA
D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002976:Clenbuterol / Q000494:pharmacology; D004734:Energy Metabolism / Q000187:drug effects / Q000502:physiology*; D066298:In Vitro Techniques; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018101:Mice, Inbred mdx; D009119:Muscle Contraction / Q000187:drug effects; D018656:Muscle Fibers, Fast-Twitch / Q000187:drug effects / Q000473:pathology / Q000502:physiology*; D018657:Muscle Fibers, Slow-Twitch / Q000187:drug effects / Q000473:pathology / Q000502:physiology*; D018482:Muscle, Skeletal / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology*; D009137:Muscular Dystrophy, Animal / Q000473:pathology / Q000503:physiopathology*; D009929:Organ Size / Q000187:drug effects
D000318:Adrenergic beta-Agonists; D002976:Clenbuterol