Journal of Applied Physiology AJP: Regulatory, Integrative and Comparative Physiology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J Appl Physiol 75: 1226-1232, 1993;
8750-7587/93 $5.00
This Article
Right arrow Full Text (PDF)
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Taillandier, D.
Right arrow Articles by Arnal, M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Taillandier, D.
Right arrow Articles by Arnal, M.

Journal of Applied Physiology, Vol 75, Issue 3 1226-1232, Copyright © 1993 by American Physiological Society

ARTICLES

Role of protein intake on protein synthesis and fiber distribution in the unweighted soleus muscle

D. Taillandier, X. Bigard, D. Desplanches, D. Attaix, C. Y. Guezennec and M. Arnal
Laboratoire d'Etude du Metabolisme Azote, Institut National de la Recherche Agronomique, Centre de Recherches de Clermont-Ferrand-Theix, Ceyrat, France.

Protein turnover in skeletal muscle is very sensitive to protein intake. To examine whether protein intake is able to affect protein synthesis in the atrophied soleus muscle, the effects of a high-protein (30%, HP) and a medium-protein (15%, MP) diet were studied in rats after 21 days of hindlimb unweighting. Three weeks of unweighting induced a sharp decrease in food intake (30%). The fractional rate of protein synthesis (ks) was determined in vivo in the slow-twitch soleus muscle by use of a flooding-dose method. With respect to pair-fed animals, a significant reduction in ks occurred (33%) in MP non-weight-bearing rats, whereas it was of lesser magnitude and not significant in HP rats. In the atrophied soleus muscle of non-weight-bearing MP rats, a large decrease (42%) in type I fiber distribution was accompanied by an increase in intermediate and type IIa fibers. By contrast, a higher percentage of type I fiber was maintained with the HP diet. However, the HP diet had no beneficial effect in preventing the decrease in either type I fiber cross-sectional area (65%) or the average decrease in absolute myofibrillar and mitochondrial volumes (69 and 52%, respectively). These results demonstrate that an HP intake did not prevent soleus muscle atrophy but may sustain protein synthesis and partly preserve fiber type distribution without affecting the ultrastructural composition of fibers. Because the circulating level of free 3,5,3'-triiodothyronine was reduced by 14% with the HP diet, this effect on fiber type distribution, and possibly protein synthesis, may involve thyroid hormones.


This article has been cited by other articles:


Home page
 J. Appl. Physiol.Home page
S. M. Phillips, E. I. Glover, and M. J. Rennie
Alterations of protein turnover underlying disuse atrophy in human skeletal muscle
J Appl Physiol, September 1, 2009; 107(3): 645 - 654.
[Abstract] [Full Text] [PDF]

Home page
 J. Nutr.Home page
K. S. Almurshed and K. K. Grunewald
Dietary Protein Does Not Affect Overloaded Skeletal Muscle in Rats
J. Nutr., July 1, 2000; 130(7): 1743 - 1748.
[Abstract] [Full Text]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online