title: Functional significance of Ca2+ in long-lasting fatigue of skeletal muscle.
abstract: Repeated activation of skeletal muscle causes fatigue, which involves a reduced ability to produce force and slowed contraction regarding both the speed of shortening and relaxation. One important component in skeletal muscle fatigue is a reduced sarcoplasmic reticulum (SR) Ca2+ release. In the present review we will describe different types of fatigue-induced inhibition of SR Ca2+ release. We will focus on a type of long-lasting failure of SR Ca2+ release which is called low-frequency fatigue, because this type of fatigue may be involved in the muscle dysfunction and chronic pain experienced by computer workers. Paradoxically it appears that the Ca2+ released from the SR, which is required for contraction, may actually be responsible for the failure of SR Ca2+ release during low-frequency fatigue. We will also discuss the relationship between gross morphological changes in muscle fibres and long-lasting failure of SR Ca2+ release. Finally, a model linking muscle cell dysfunction and muscle pain is proposed.
authors: Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden. hakan.westerblad@fyfa.ki.se
authors: H
authors: H
authors: Westerblad
authors: J D
authors: JD
authors: Bruton
authors: D G
authors: DG
authors: Allen
authors: J
authors: J
authors: Lännergren
mesh_terms: D002118:Calcium / Q000378:metabolism / Q000502:physiology*; D020013:Calcium Signaling / Q000502:physiology*; D006801:Humans; D018763:Muscle Fatigue / Q000502:physiology*; D018482:Muscle, Skeletal / Q000378:metabolism / Q000502:physiology*; D012519:Sarcoplasmic Reticulum / Q000378:metabolism
chemical_list: D002118:Calcium