Imaging Analysis of the Neuromuscular Junction in Dystrophic Muscle

  • Stephen J. P. Pratt
  • Shama R. Iyer
  • Sameer B. Shah
  • Richard M. Lovering
Part of the Methods in Molecular Biology book series (MIMB, volume 1687)


Duchenne muscular dystrophy (DMD), caused by the absence of the protein dystrophin, is characterized as a neuromuscular disease in which muscle weakness, increased susceptibility to muscle injury, and inadequate repair appear to underlie the pathology. Considerable attention has been dedicated to studying muscle fiber damage, but there is little information to determine if damage from contraction-induced injury also occurs at or near the nerve terminal axon. Interestingly, both human patients and the mouse model for DMD (the mdx mouse) present fragmented neuromuscular junction (NMJ) morphology. Studies of mdx mice have revealed presynaptic and postsynaptic abnormalities, nerve terminal discontinuity, as well as increased susceptibility of the NMJ to contraction-induced injury with corresponding functional changes in neuromuscular transmission and nerve-evoked electromyography. Focusing on the NMJ as a contributor to functional deficits in the muscle represents a paradigm shift from the more prevalent myocentric perspectives. Further studies are needed to determine the extent to which the nerve-muscle interaction is disrupted in DMD and the role of the NMJ in the dystrophic progression. This chapter lists the tools needed for nerve terminal and NMJ structural analysis using fluorescence imaging, and provides a step-by-step outline for how to stain, image, and analyze the NMJ in skeletal muscle, with specific attention to mdx muscle.

Key words

Skeletal muscle Neuromuscular junction NMJ structure NMJ occupancy NMJ area Duchenne muscular dystrophy Bungarotoxin mdx 



This work was supported by grants from the National Institutes of Health by grants to S.R.I. (AR07592-20), and to R.M.L. (R01-AR059179 and R21-AR067872-01).


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Copyright information

© Springer Science+Business Media LLC 2018

Authors and Affiliations

  • Stephen J. P. Pratt
    • 1
  • Shama R. Iyer
    • 2
  • Sameer B. Shah
    • 3
    • 5
  • Richard M. Lovering
    • 2
    • 4
  1. 1.Department of Biochemistry and Molecular BiologyUniversity of Maryland, Baltimore School of MedicineBaltimoreUSA
  2. 2.Department of OrthopaedicsUniversity of Maryland, Baltimore School of MedicineBaltimoreUSA
  3. 3.Departments of Orthopaedic Surgery and BioengineeringUniversity of California San DiegoLa JollaUSA
  4. 4.Department of PhysiologyUniversity of Maryland, Baltimore School of MedicineBaltimoreUSA
  5. 5.Research DivisionVeterans Administration San Diego Healthcare SystemSan DiegoUSA

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