Pflügers Archiv

, Volume 440, Issue 5, pp 727–734

Hypoxia and fatigue-induced modification of function and proteins in intact and skinned murine diaphragm muscle

  • Marco A. de Paula Brotto
  • Sheila Andreatta-van Leyen
  • Christopher M. Nosek
  • Leticia S. Brotto
  • Thomas M. Nosek
Original Article

DOI: 10.1007/s004240000327

Cite this article as:
de Paula Brotto, M.A., Andreatta-van Leyen, S., Nosek, C.M. et al. Pflügers Arch - Eur J Physiol (2000) 440: 727. doi:10.1007/s004240000327

Abstract

Fatigue studies of isolated, intact muscles typically utilize solutions saturated with O2. However, under in vivo fatiguing conditions, less oxygen is delivered to the muscles and they actually experience hypoxia. No studies to date have correlated the effects of acute hypoxia on the isometric contractile properties of intact muscles, skinned fibers isolated from the same muscles, and the cellular content of specific muscle proteins. Therefore, we have studied the effects of in vitro acute hypoxia on the fatigability of intact diaphragm muscle strips and on the isometric contractile properties of single Triton-skinned fibers isolated from control and hypoxic diaphragm muscles. We found that hypoxia and fatiguing stimulation per se affect the tetanic force of intact muscle strips without exhibiting any significant deleterious effects on the calcium-activated force of skinned muscle fibers dissected from the intact muscles. In contrast, fatiguing stimulation under hypoxic conditions decreased both the tetanic force of muscle strips and the calcium-activated force of skinned muscle fibers. Gel electrophoresis of muscles subjected to hypoxia and hypoxic-fatigue revealed that there is a significant reduction in three protein bands when compared to control muscles. Protein modification may be the underlying mechanism of muscle fatigue under physiologic conditions.

Calcium Diaphragm Fatigue Hypoxia Mouse Muscle Proteins Reactive oxygen species SDS-PAGE Skinned fibers 

Copyright information

© Springer-Verlag 2000

Authors and Affiliations

  • Marco A. de Paula Brotto
    • 1
  • Sheila Andreatta-van Leyen
    • 1
  • Christopher M. Nosek
    • 1
  • Leticia S. Brotto
    • 1
  • Thomas M. Nosek
    • 1
  1. 1.Muscle Cell Biology Research Group, Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, Ohio 44106USA