Journal of Applied Physiology Ad Instruments
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J Appl Physiol 93: 1437-1447, 2002. First published June 30, 2002; doi:10.1152/japplphysiol.00189.2002
8750-7587/02 $5.00
This Article
Right arrow Full Text Free
Right arrow Full Text (PDF) Free
Right arrow All Versions of this Article:
93/4/1437    most recent
00189.2002v1
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
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in Web of Science
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 Web of Science (17)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Chen, C.-M.
Right arrow Articles by Smith, H. K.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Chen, C.-M.
Right arrow Articles by Smith, H. K.
Vol. 93, Issue 4, 1437-1447, October 2002

Effects of botulinum toxin A injection and exercise on the growth of juvenile rat gastrocnemius muscle

Chen-Ming Chen1, N. Susan Stott2, and Heather K. Smith1

Departments of 1 Sport and Exercise Science and 2 Surgery, University of Auckland, Auckland 1020, New Zealand

Botulinum toxin A (Btx) injections and supervised exercise are often used concurrently to treat calf muscle spasticity in children. This study has analyzed the early effects of Btx-induced paralysis and increased activity by voluntary wheel running on cell growth-related processes in juvenile rat gastrocnemius muscle. Btx injection at 29 days of age prevented the normal increases in wet mass (50%) and fiber cross-sectional area (34%) seen by 36 days of age in control rats. Btx-injected vs. contralateral muscles had 22% fewer myonuclei per fiber length but greater than twofold the number of MyoD-positive nuclei at 36 days of age. The accretion of 5-bromo-2'-deoxyuridine-labeled newly produced myonuclei did not differ between limbs. Voluntary exercise during the 7 days increased the mass (18%) and fiber size (23%) of Btx-injected and contralateral muscles but did not affect any other variable. Thus Btx injection and exercise had early effects on muscle and fiber size without consistently associated changes in myonuclear production or number. This suggests the presence of noncontractile activity-dependent, growth-promoting cytoplasmic events in juvenile muscle.

voluntary wheel running; satellite cells; MyoD; myonuclear number; fiber size


This article has been cited by other articles:


Home page
 Exp PhysiolHome page
M. Velders, K. Legerlotz, S. J. Falconer, N. S. Stott, C. D. McMahon, and H. K. Smith
Effect of botulinum toxin A-induced paralysis and exercise training on mechanosensing and signalling gene expression in juvenile rat gastrocnemius muscle
Exp Physiol, December 1, 2008; 93(12): 1273 - 1283.
[Abstract] [Full Text] [PDF]

Home page
 IOVSHome page
I. Ugalde, S. P. Christiansen, and L. K. McLoon
Botulinum Toxin Treatment of Extraocular Muscles in Rabbits Results in Increased Myofiber Remodeling
Invest. Ophthalmol. Vis. Sci., November 1, 2005; 46(11): 4114 - 4120.
[Abstract] [Full Text] [PDF]

Home page
 J. Cell Sci.Home page
A. S. Brack, H. Bildsoe, and S. M. Hughes
Evidence that satellite cell decrement contributes to preferential decline in nuclear number from large fibres during murine age-related muscle atrophy
J. Cell Sci., October 15, 2005; 118(20): 4813 - 4821.
[Abstract] [Full Text] [PDF]


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