Chemical energetics of slow- and fast-twitch muscles of the mouse

Michael T. Crow, Martin J. Kushmerick

Research output: Contribution to journalArticlepeer-review

Abstract

The energy utilization associated with contraction was measured in isolated slow- and fast-twitch muscles of the mouse at 20°C The extent of this utilization was estimated from either the extent of high-energy phosphate splitting occurring during contraction (the initial chemical change, Δ - Pinit) or from the extent of recovery resynthesis calculated from the observed oxygen consumption and lactate production occurring during the recovery period (recovery chemical resynthesis, Δ - Prec). For short tetani, the cost to maintain isometric tension in the fast-twitch extensor digitorum longus (EDL) was approximately threefold greater than that in the slow-twitch soleus. With prolonged stimulation, however, the energy cost in the EDL diminished so that after 12 s of stimulation, the energy cost in the EDL was only 50% greater than that of the soleus. For both the slow-twitch soleus and the fast-twitch EDL and for all tetanus durations (up to 15 s), the extent of the initial chemical change was identical with the amount of recovery chemical resynthesis, showing that a biochemical energy balance existed in these muscles.

Original languageEnglish (US)
Pages (from-to)147-166
Number of pages20
JournalJournal of General Physiology
Volume79
Issue number1
DOIs
StatePublished - Jan 1 1982
Externally publishedYes

ASJC Scopus subject areas

  • Physiology

Fingerprint

Dive into the research topics of 'Chemical energetics of slow- and fast-twitch muscles of the mouse'. Together they form a unique fingerprint.

Cite this