Contractile properties of slow and fast skeletal muscles from protease activated receptor-1 null mice.
Muscle Nerve
; 50(6): 991-8, 2014 Dec.
Article
em En
| MEDLINE
| ID: mdl-24692104
ABSTRACT
INTRODUCTION:
Protease-activated receptors (PARs) may play a role in skeletal muscle development. We compared the contractile properties of slow-twitch soleus muscles and fast-twitch extensor digitorum longus (EDL) muscles from PAR-1 null and littermate control mice.METHODS:
Contractile function was measured using a force transducer system. Fiber type proportions were determined using immunohistochemistry.RESULTS:
Soleus muscles from PAR-1 null mice exhibited longer contraction times, a leftward shift in the force-stimulation frequency relationship, and decreased fatiguability compared with controls. PAR-1 null soleus muscles also had increased type 1 and decreased type IIb/x fiber numbers compared with controls. In PAR-1 null EDL muscles, no differences were found, except for a slower rate of fatigue compared with controls.CONCLUSIONS:
The absence of PAR-1 results in a slower skeletal muscle contractile phenotype, likely due to an increase in type I and a decrease in type IIb/x fiber numbers. Muscle Nerve 50 991-998, 2014.Palavras-chave
Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Músculo Esquelético
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Fibras Musculares de Contração Lenta
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Fibras Musculares de Contração Rápida
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Receptor PAR-1
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Contração Muscular
Limite:
Animals
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article