Biochemical response to chronic shortening in unloaded soleus muscles

S. R. Jaspers, J. M. Fagan, M. E. Tischler

Research output: Contribution to journalArticle

22 Scopus citations

Abstract

One leg of tail-casted suspended rats was immobilized in a plantar-flexed position to test whether chronic shortening of posterior leg muscles affected the metabolic response to unloading. The immobilized plantaris and gastrocnemius muscles of these animals showed ~ 20% loss of muscle mass in contrast to simply a slower growth rate with unloading. Loss of mass of the soleus muscle during suspension was not accentuated by chronic shortening. Although protein degradation in the isolated soleus muscle of the plantar-flexed limb was slightly faster than in the contralateral free limb, this difference was offset by faster synthesis of the myofibrillar protein fraction of the chronically shortened muscle. Total adenine nucleotides were 17% lower (P < 0.005) in the chronically shortened soleus muscle following incubation. Glutamate, glutamine, and alanine metabolism showed little response to chronic shortening. These results suggest that, in the soleus muscle, chronic shortening did not alter significantly the metabolic response to unloading and reduced activity.

Original languageEnglish (US)
Pages (from-to)1159-1163
Number of pages5
JournalJournal of Applied Physiology
Volume59
Issue number4
StatePublished - Dec 1 1985

ASJC Scopus subject areas

  • Physiology
  • Physiology (medical)

Fingerprint Dive into the research topics of 'Biochemical response to chronic shortening in unloaded soleus muscles'. Together they form a unique fingerprint.

  • Cite this