Neuromuscular Junction Morphology and Gene Dysregulation in the Wobbler Model of Spinal Neurodegeneration

J Mol Neurosci. 2018 Sep;66(1):114-120. doi: 10.1007/s12031-018-1153-8. Epub 2018 Aug 13.

Abstract

Amyotrophic lateral sclerosis (ALS) is the most common adult-onset neuromuscular disease for which there is currently no effective treatment. The progression of ALS includes loss of motor neurons controlling the voluntary muscles, with much of this loss occurring at the neuromuscular junction. In an effort to better understand changes at the neuromuscular junction, we utilized the wobbler mouse model of motor neuron loss. We examined biceps and end plate morphologies and monitored selected factors involved in end plate function. Structural volumes were determined from 3D reconstructions that were generated for the end plates. Wobbler mice exhibited size reductions of both the muscle fibers and the end plates within the biceps, and we found that the end plate volumes were the most sensitive indicator of the degeneration. Concurrently, we found increases in calcitonin gene-related peptide (CGRP) and its receptor in wobbler biceps and spinal cord. We also found increases in gene expression of two acetylcholine receptors within the wobbler biceps, which may be a result of altered CGRP/CALCRL (calcitonin receptor-like receptor) expression.

Keywords: Calcitonin gene-related peptide (CGRP); End plate; Motor neuron disease; Neuromuscular junction; Wobbler mice.

MeSH terms

  • Animals
  • Calcitonin Gene-Related Peptide / genetics
  • Calcitonin Gene-Related Peptide / metabolism
  • Mice
  • Motor Endplate / metabolism
  • Motor Endplate / pathology*
  • Motor Neurons / metabolism
  • Motor Neurons / pathology
  • Neurodegenerative Diseases / genetics
  • Neurodegenerative Diseases / metabolism
  • Neurodegenerative Diseases / pathology*
  • Receptors, Cholinergic / genetics
  • Receptors, Cholinergic / metabolism
  • Vesicular Transport Proteins / genetics*

Substances

  • Receptors, Cholinergic
  • Vesicular Transport Proteins
  • Vps54 protein, mouse
  • Calcitonin Gene-Related Peptide