Intracellular Acidosis Enhances the Excitability of Working Muscle

@article{Pedersen2004IntracellularAE,
  title={Intracellular Acidosis Enhances the Excitability of Working Muscle},
  author={T H Pedersen and Ole Bjorslev Nielsen and Graham D Lamb and D. George Stephenson},
  journal={Science},
  year={2004},
  volume={305},
  pages={1144 - 1147}
}
Intracellular acidification of skeletal muscles is commonly thought to contribute to muscle fatigue. However, intracellular acidosis also acts to preserve muscle excitability when muscles become depolarized, which occurs with working muscles. Here, we show that this process may be mediated by decreased chloride permeability, which enables action potentials to still be propagated along the internal network of tubules in a muscle fiber (the T system) despite muscle depolarization. These results… Expand
Increased Excitability of Acidified Skeletal Muscle
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TLDR
These findings require us to reevaluate the notions of lactic acid, acidosis and muscular fatigue and a proposal that lactate production retards, not causes, acidotic disease. Expand
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TLDR
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TLDR
Most of the mechanistic studies of fatigue are on isolated animal tissues, and another major challenge is to use the knowledge generated in these studies to identify the mechanisms of fatigue in intact animals and particularly in human diseases. Expand
Lactate Is Not a Cause of Fatigue
For many years, it has generally been believed that the accumulations of lactate (lactic acid) in muscles and in the central nervous system are associated with peripheral and central nervous systemExpand
Chloride Channels Take Center Stage in Acute Regulation of Excitability in Skeletal Muscle: Implications for Fatigue.
TLDR
Current knowledge about the acute regulation of ClC-1 channels in active muscles and its importance for muscle excitability, function, and fatigue is reviewed. Expand
Regulation of Na+-K+ homeostasis and excitability in contracting muscles: implications for fatigue.
  • O. B. Nielsen, F. D. de Paoli
  • Chemistry, Medicine
  • Applied physiology, nutrition, and metabolism = Physiologie appliquee, nutrition et metabolisme
  • 2007
TLDR
Parts of the regulation of Na+-K+ homeostasis and excitability in contracting muscles is discussed within this context, together with the implications for the contractile function of skeletal muscles. Expand
Lactate and force production in skeletal muscle
TLDR
It is concluded that although lactate/lactic acid incubation regains force in K+‐depressed resting muscle, a similar incubation has no or a negative effect on force development in active muscle. Expand
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