High temperature does not alter fatigability in intact mouse skeletal muscle fibres.

Details

Serval ID
serval:BIB_0AD7150C9CF4
Type
Article: article from journal or magazin.
Collection
Publications
Title
High temperature does not alter fatigability in intact mouse skeletal muscle fibres.
Journal
Journal of Physiology
Author(s)
Place N., Yamada T., Zhang S.J., Westerblad H., Bruton J.D.
ISSN
1469-7793 (Electronic)
ISSN-L
0022-3751
Publication state
Published
Issued date
2009
Volume
587
Number
Pt 19
Pages
4717-4724
Language
english
Abstract
Intense activation of skeletal muscle results in fatigue development, which involves impaired function of the muscle cells resulting in weaker and slower contractions. Intense muscle activity also results in increased heat production and muscle temperature may rise by up to 6 degrees C. Hyperthermia is associated with impaired exercise performance in vivo and recent studies have shown contractile dysfunction and premature fatigue development in easily fatigued muscle fibres stimulated at high temperatures and these defects were attributed to oxidative stress. Here we studied whether fatigue-resistant soleus fibres stimulated at increased temperature show premature fatigue development and whether increasing the level of oxidative stress accelerates fatigue development. Intact single fibres or small bundles of soleus fibres were fatigued by 600 ms tetani given at 2 s intervals at 37 degrees C and 43 degrees C, which is the highest temperature the muscle would experience in vivo. Tetanic force in the unfatigued state was not significantly different at the two temperatures. With 100 fatiguing tetani, force decreased by approximately 15% at both temperatures; the free cytosolic [Ca(2+)] (assessed with indo-1) showed a similar approximately 10% decrease at both temperatures. The oxidative stress during fatigue at 43 degrees C was increased by application of 10 microM hydrogen peroxide or tert-butyl hydroperoxide and this did not cause premature fatigue development. In summary, fatigue-resistant muscle fibres do not display impaired contractility and fatigue resistance at the highest temperature that mammals, including humans, would experience in vivo. Thus, intrinsic defects in fatigue-resistant muscle fibres cannot explain the decreased physical performance at high temperatures.
Keywords
Animals, Calcium/metabolism, Electric Stimulation, Exercise/physiology, Fever/physiopathology, Humans, Hydrogen Peroxide/pharmacology, Male, Mice, Muscle Contraction/drug effects, Muscle Contraction/physiology, Muscle Fatigue/drug effects, Muscle Fatigue/physiology, Muscle Fibers, Skeletal/drug effects, Muscle Fibers, Skeletal/physiology, Oxidative Stress, Temperature, tert-Butylhydroperoxide/pharmacology
Pubmed
Web of science
Open Access
Yes
Create date
20/09/2013 8:38
Last modification date
20/08/2019 12:32
Usage data