Incubating isolated mouse EDL muscles with creatine improves force production and twitch kinetics in fatigue due to reduction in ionic strength.

BACKGROUND: Creatine supplementation can improve performance during high intensity exercise in humans and improve muscle strength in certain myopathies. In this present study, we investigated the direct effects of acute creatine incubation on isolated mouse fast-twitch EDL muscles, and examined how...

Full description

Bibliographic Details
Main Authors: Stewart I Head, Bronwen Greenaway, Stephen Chan
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2011-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC3151260?pdf=render
_version_ 1818026241017511936
author Stewart I Head
Bronwen Greenaway
Stephen Chan
author_facet Stewart I Head
Bronwen Greenaway
Stephen Chan
author_sort Stewart I Head
collection DOAJ
description BACKGROUND: Creatine supplementation can improve performance during high intensity exercise in humans and improve muscle strength in certain myopathies. In this present study, we investigated the direct effects of acute creatine incubation on isolated mouse fast-twitch EDL muscles, and examined how these effects change with fatigue. METHODS AND RESULTS: The extensor digitorum longus muscle from mice aged 12-14 weeks was isolated and stimulated with field electrodes to measure force characteristics in 3 different states: (i) before fatigue; (ii) immediately after a fatigue protocol; and (iii) after recovery. These served as the control measurements for the muscle. The muscle was then incubated in a creatine solution and washed. The measurement of force characteristics in the 3 different states was then repeated. In un-fatigued muscle, creatine incubation increased the maximal tetanic force. In fatigued muscle, creatine treatment increased the force produced at all frequencies of stimulation. Incubation also increased the rate of twitch relaxation and twitch contraction in fatigued muscle. During repetitive fatiguing stimulation, creatine-treated muscles took 55.1±9.5% longer than control muscles to lose half of their original force. Measurement of weight changes showed that creatine incubation increased EDL muscle mass by 7%. CONCLUSION: Acute creatine application improves force production in isolated fast-twitch EDL muscle, and these improvements are particularly apparent when the muscle is fatigued. One likely mechanism for this improvement is an increase in Ca(2+) sensitivity of contractile proteins as a result of ionic strength decreases following creatine incubation.
first_indexed 2024-12-10T04:28:52Z
format Article
id doaj.art-1cbf34c2814d4b9d97d86228e4c3ac00
institution Directory Open Access Journal
issn 1932-6203
language English
last_indexed 2024-12-10T04:28:52Z
publishDate 2011-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj.art-1cbf34c2814d4b9d97d86228e4c3ac002022-12-22T02:02:13ZengPublic Library of Science (PLoS)PLoS ONE1932-62032011-01-0168e2274210.1371/journal.pone.0022742Incubating isolated mouse EDL muscles with creatine improves force production and twitch kinetics in fatigue due to reduction in ionic strength.Stewart I HeadBronwen GreenawayStephen ChanBACKGROUND: Creatine supplementation can improve performance during high intensity exercise in humans and improve muscle strength in certain myopathies. In this present study, we investigated the direct effects of acute creatine incubation on isolated mouse fast-twitch EDL muscles, and examined how these effects change with fatigue. METHODS AND RESULTS: The extensor digitorum longus muscle from mice aged 12-14 weeks was isolated and stimulated with field electrodes to measure force characteristics in 3 different states: (i) before fatigue; (ii) immediately after a fatigue protocol; and (iii) after recovery. These served as the control measurements for the muscle. The muscle was then incubated in a creatine solution and washed. The measurement of force characteristics in the 3 different states was then repeated. In un-fatigued muscle, creatine incubation increased the maximal tetanic force. In fatigued muscle, creatine treatment increased the force produced at all frequencies of stimulation. Incubation also increased the rate of twitch relaxation and twitch contraction in fatigued muscle. During repetitive fatiguing stimulation, creatine-treated muscles took 55.1±9.5% longer than control muscles to lose half of their original force. Measurement of weight changes showed that creatine incubation increased EDL muscle mass by 7%. CONCLUSION: Acute creatine application improves force production in isolated fast-twitch EDL muscle, and these improvements are particularly apparent when the muscle is fatigued. One likely mechanism for this improvement is an increase in Ca(2+) sensitivity of contractile proteins as a result of ionic strength decreases following creatine incubation.http://europepmc.org/articles/PMC3151260?pdf=render
spellingShingle Stewart I Head
Bronwen Greenaway
Stephen Chan
Incubating isolated mouse EDL muscles with creatine improves force production and twitch kinetics in fatigue due to reduction in ionic strength.
PLoS ONE
title Incubating isolated mouse EDL muscles with creatine improves force production and twitch kinetics in fatigue due to reduction in ionic strength.
title_full Incubating isolated mouse EDL muscles with creatine improves force production and twitch kinetics in fatigue due to reduction in ionic strength.
title_fullStr Incubating isolated mouse EDL muscles with creatine improves force production and twitch kinetics in fatigue due to reduction in ionic strength.
title_full_unstemmed Incubating isolated mouse EDL muscles with creatine improves force production and twitch kinetics in fatigue due to reduction in ionic strength.
title_short Incubating isolated mouse EDL muscles with creatine improves force production and twitch kinetics in fatigue due to reduction in ionic strength.
title_sort incubating isolated mouse edl muscles with creatine improves force production and twitch kinetics in fatigue due to reduction in ionic strength
url http://europepmc.org/articles/PMC3151260?pdf=render
work_keys_str_mv AT stewartihead incubatingisolatedmouseedlmuscleswithcreatineimprovesforceproductionandtwitchkineticsinfatigueduetoreductioninionicstrength
AT bronwengreenaway incubatingisolatedmouseedlmuscleswithcreatineimprovesforceproductionandtwitchkineticsinfatigueduetoreductioninionicstrength
AT stephenchan incubatingisolatedmouseedlmuscleswithcreatineimprovesforceproductionandtwitchkineticsinfatigueduetoreductioninionicstrength