In Vivo Assessment of Mouse Hindlimb Muscle Force, Contractile, and Fatigue Characteristics, and Motor Unit Number

Bernadett Kalmar1, Linda Greensmith1

1 UCL Institute of Neurology, London, United Kingdom
Publication Name:  Current Protocols in Mouse Biology
Unit Number:   
DOI:  10.1002/9780470942390.mo110155
Online Posting Date:  March, 2012
GO TO THE FULL TEXT: PDF or HTML at Wiley Online Library

Abstract

The use of rodents to model neuromuscular diseases necessitates assessment of neuromuscular function to monitor disease progression. Muscle function can be assessed by determining muscle force, and the contraction's contractile and fatigue characteristics. Assessment of motor units gives a measure of motoneuron health. Thus, assessment of these parameters can reveal the degree and nature of neuromuscular pathology. A reduction in muscle force may result either from loss of motoneurons and a concomitant denervation of muscles or as a result of primary muscle pathology. Estimation of the number of functional motor units may identify whether the deficit is neural in origin. Here, we give a detailed description of the assessment of muscle force, contractile characteristics, and muscle fatigue, as well as a method that gives a direct and accurate readout on the number of motor units in individual mouse hindlimb muscles in mice—now widely used to model a variety of neuromuscular disorders. Curr. Protoc. Mouse Biol. 2:89‐101 © 2012 by John Wiley & Sons, Inc.

Keywords: muscle force; muscle fatigue; muscle contraction; motor unit; motoneuron; twitch force

     
 
GO TO THE FULL PROTOCOL:
PDF or HTML at Wiley Online Library

Table of Contents

  • Introduction
  • Basic Protocol 1: Surgical Preparation of Mouse Hindlimb Muscles for Physiological Recordings
  • Basic Protocol 2: Physiological Recording of Single‐Twitch Contractions to Determine Single‐Twitch Force and Time Characteristics of Single‐Twitch Contractions in Mouse Muscles
  • Basic Protocol 3: Physiological Recording of Motor Units in the EDL Muscle of the Mouse
  • Commentary
  • Literature Cited
  • Figures
  • Tables
     
 
GO TO THE FULL PROTOCOL:
PDF or HTML at Wiley Online Library

Materials

Basic Protocol 1: Surgical Preparation of Mouse Hindlimb Muscles for Physiological Recordings

  Materials
  • Chloral hydrate (Sigma‐Aldrich, cat. no. C8383)
  • Mice of any size, age, or gender
  • Sterile saline
  • Weighing scales to determine animal weight
  • 1‐ml syringe equipped with a 27‐G needle
  • Shaver
  • Surgical blades
  • Fine silk thread
  • Cork dissecting board
  • Forceps
  • Scissors
  • Scalpel (no. 15)
  • Steel pins
  • Cotton swabs
  • Metal clamps
  • Solid metal table to reduce “noise” in the recordings

Basic Protocol 2: Physiological Recording of Single‐Twitch Contractions to Determine Single‐Twitch Force and Time Characteristics of Single‐Twitch Contractions in Mouse Muscles

  Materials
  • Animal prepared for physiological recording (see protocol 1)
  • 2 UF1 force sensor strain‐gauge transducers (LCM Systems) within the 5 g to 180 g range
  • 2 Platinum electrodes made out of 0.36‐mm diameter platinum wires
  • Constant Voltage Stimulator (Type DS2, Digitimer)
  • Digitimer D4030 pulse generator (Digitimer)
  • Lectromed Multitrace Chart Recorder (Lectromed Instruments)
  • Electronic Digital Oscilloscope (Type Picoscope 3424 by Pico Technology)
  • PC with a Windows XP operating system and Picoscope software version 5.2 installed
GO TO THE FULL PROTOCOL:
PDF or HTML at Wiley Online Library

Figures

Videos

Literature Cited

Literature Cited
   Attal, P., Lambert, F., Marchand‐Adam, S., Bobin, S., Pourny, J.C., Chemla, D., Lecarpentier, Y., and Coirault, C. 2000. Severe mechanical dysfunction in pharyngeal muscle from adult mdx mice. Am. J. Respir. Crit. Care Med. 162:278‐281.
   Bacou, F. and Vigneron, P. 1988. Properties of skeletal muscle fibers. Influence of motor innervation. Reprod. Nutr. Dev. 28:1387‐1453.
   Bagust, J., Knott, S., Lewis, D.M. Luck, J.C., and Westerman, R.A. 1973. Isometric contractions of motor units in a fast twitch muscle of the cat. J. Physiol. 231:87‐104.
   Betz, W.J., Caldwell, J.H., and Ribchester, R.R. 1979. The size of motor units during post‐natal development of rat lumbrical muscle. J. Physiol. 297:463‐478.
   Brown, W.F. 1972. A method for estimating the number of motor units in thenar muscles and the changes in motor unit count with ageing. J. Neurol. Neurosurg. Psychiatry 35:845‐852.
   Burke, R.E., Levine, D.N., Tsairis, P., and Zajac, F.E. 3rd. 1973. Physiological types and histochemical profiles in motor units of the cat gastrocnemius. J. Physiol. 234:723‐748.
   Burke, R.E., Levine, D.N., Salcman, M., and Tsairis, P. 1974. Motor units in cat soleus muscle: Physiological, histochemical and morphological characteristics. J. Physiol. 238:503‐514.
   Kalmar, B., Novoselov, S., Gray, A., Cheetham, M.E., Margulis, B., and Greensmith, L. 2008. Late stage treatment with arimoclomol delays disease progression and prevents protein aggregation in the SOD1 mouse model of ALS. J. Neurochem. 107:339‐350.
   Litvinova, K.S., Tarakin, P.P., Fokina, N.M., Istomina, V.E., Larina, I.M., and Shenkman, B.S. 2007. Reloading of rat soleus after hindlimb unloading and serum insulin‐like growth factor 1. Ross. Fiziol. Zh. Im. I. M. Sechenova 93:1143‐1155.
   Louboutin, J.P., Fichter‐Gagnepain, V., Pastoret, C., Thaon, E., Noireaud, J., Sebille, A., and Fardeau, M. 1995. Morphological and functional study of extensor digitorum longus muscle regeneration after iterative crush lesions in mdx mouse. Neuromuscul. Disord. 5:489‐500.
   Lowrie, M.B. and Vrbova, G. 1984. Different pattern of recovery of fast and slow muscles following nerve injury in the rat. J. Physiol. 349:397‐410.
   McComas, A.J. 1991. Invited review: Motor unit estimation: Methods, results, and present status. Muscle Nerve 14:585‐597.
   McComas, A.J., Fawcett, P.R., Campbell, M.J., and Sica, R.E. 1971. Electrophysiological estimation of the number of motor units within a human muscle. J. Neurol. Neurosurg. Psychiatry 34:121‐131.
   Pastoret, C. and Sebille, A. 1993. Time course study of the isometric contractile properties of mdx mouse striated muscles. J. Muscle Res. Cell Motil. 14:423‐431.
   Rafuse, V.F., Pattullo, M.C., and Gordon, T. 1997. Innervation ratio and motor unit force in large muscles: A study of chronically stimulated cat medial gastrocnemius. J. Physiol. 499:809‐823.
   Salmons, S. and Vrbova, G. 1969. The influence of activity on some contractile characteristics of mammalian fast and slow muscles. J. Physiol. 201:535‐549.
   Sharp, P.S., Dick, J.R., and Greensmith, L. 2005. The effect of peripheral nerve injury on disease progression in the SOD1(G93A) mouse model of amyotrophic lateral sclerosis. Neuroscience 130:897‐910.
   Spurney, C.F., Gordish‐Dressman, H., Guerron, A.D., Sali, A., Pandey, G.S., Rawat, R., Van Der Meulen, J.H., Cha, H.J., Pistilli, E.E., Partridge, T.A., Hoffman, E.P., and Nagaraju, K. 2009. Preclinical drug trials in the mdx mouse: assessment of reliable and sensitive outcome measures. Muscle Nerve 39:591‐602.
GO TO THE FULL PROTOCOL:
PDF or HTML at Wiley Online Library