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PubMed · 6628627

Electrophysiologic differences between mouse extensor digitorum longus and soleus.

J A Florendo·J F Reger·P K Law
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Abstract

Miniature end-plate potentials (MEPPs) and indirectly elicited action potentials were recorded in vivo at 37 degrees C from surface fibers of the fast-twitch extensor digitorum longus (EDL) and the slow-twitch soleus (SOL) muscles of 3- to 4-month-old Bar Harbor 129 mice. The EDL MEPPs exhibited a significantly higher frequency, smaller amplitude, and shorter duration than the MEPPs of the SOL. Action potentials of EDL fibers exhibited a significantly greater amplitude and shorter duration than SOL fibers. A single stimulus elicited several action potentials from an EDL fiber but only one action potential from a SOL fiber. Fast- and slow-twitch muscle fibers can thus be identified and distinguished on the basis of these electrophysiologic parameters. There was no significant difference in resting membrane potentials between EDL and SOL fibers.

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Action PotentialsAnimalsElectrophysiologyHindlimbMiceMice, Inbred StrainsMotor EndplateMusclesToesJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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J A Florendo, J F Reger, P K Law. 1983. Electrophysiologic differences between mouse extensor digitorum longus and soleus.. https://doi.org/10.1016/0014-4886(83)90412-0

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