Temperature Effects on Force and Actin–Myosin Interaction in Muscle: A Look Back on Some Experimental Findings

K. W. Ranatunga*

*Corresponding author for this work

Research output: Contribution to journalReview article (Academic Journal)peer-review

10 Citations (Scopus)
182 Downloads (Pure)

Abstract

Observations made in temperature studies on mammalian muscle during force development, shortening, and lengthening, are re-examined. The isometric force in active muscle goes up substantially on warming from less than 10°C to temperatures closer to physiological (>30°C), and the sigmoidal temperature dependence of this force has a half-maximum at ~10°C. During steady shortening, when force is decreased to a steady level, the sigmoidal curve is more pronounced and shifted to higher temperatures, whereas, in lengthening muscle, the curve is shifted to lower temperatures, and there is a less marked increase with temperature. Even with a small rapid temperature-jump (T-jump), force in active muscle rises in a definitive way. The rate of tension rise is slower with adenosine diphosphate (ADP) and faster with increased phosphate. Analysis showed that a T-jump enhances an early, pre-phosphate release step in the acto-myosin (crossbridge) ATPase cycle, thus inducing a force-rise. The sigmoidal dependence of steady force on temperature is due to this endothermic nature of crossbridge force generation. During shortening, the force-generating step and the ATPase cycle are accelerated, whereas during lengthening, they are inhibited. The endothermic force generation is seen in different muscle types (fast, slow, and cardiac). The underlying mechanism may involve a structural change in attached myosin heads and/or their attachments on heat absorption.
Original languageEnglish
Article number1538
Number of pages24
JournalInternational Journal of Molecular Sciences
Volume19
Issue number5
Early online date22 May 2018
DOIs
Publication statusPublished - May 2018

Keywords

  • Actin-myosin
  • Crossbridge cycle
  • Crossbridge force
  • Endothermic force
  • Muscle force
  • Muscle shortening
  • Temperature-sensitivity

Fingerprint

Dive into the research topics of 'Temperature Effects on Force and Actin–Myosin Interaction in Muscle: A Look Back on Some Experimental Findings'. Together they form a unique fingerprint.

Cite this