Synaptic vesicle morphology and recycling are altered in myenteric neurons of mice lacking dystrophin (mdx mice).
Several dystrophin isoforms are known. The full-length isoform is present in striated and smooth muscles and neurons and its lack causes Duchenne Muscular Dystrophy, a progressive myopathy accompanied by mild cognitive deficits and gastrointestinal dismotility. An ultrastructural study was undertaken in the colon of mice lacking full-length dystrophin and maintaining shorter isoforms (mdx mice) to ascertain whether myenteric neurons have an altered morphology. Results showed a significant increase in the size of synaptic vesicle and in the number of recycling vesicles. An enlargement of endoplasmic reticulum cisternae in a subpopulation of neurons was also seen. Immunohistochemistry confirmed that the shorter isoforms were expressed in mdx mice myenteric neurons. These findings indicate the presence of a neuropathy at the myenteric plexus which might justify the defective neuronal control of gastrointestinal motility reported for these animals and which might be correlated with full-length dystrophin loss, since the shorter isoforms are present.
D000818:Animals; D003106:Colon / Q000294:innervation* / Q000473:pathology / Q000503:physiopathology; D004195:Disease Models, Animal; D016189:Dystrophin / Q000172:deficiency* / Q000235:genetics; D004721:Endoplasmic Reticulum / Q000378:metabolism / Q000473:pathology / Q000648:ultrastructure; D005767:Gastrointestinal Diseases / Q000235:genetics / Q000473:pathology / Q000503:physiopathology; D005769:Gastrointestinal Motility / Q000235:genetics; D007150:Immunohistochemistry; D007425:Intracellular Membranes / Q000378:metabolism / Q000473:pathology / Q000648:ultrastructure; D051379:Mice; D008810:Mice, Inbred C57BL; D018101:Mice, Inbred mdx; D008854:Microscopy, Electron; D008970:Molecular Weight; D020388:Muscular Dystrophy, Duchenne / Q000150:complications; D009154:Mutation / Q000235:genetics; D009197:Myenteric Plexus / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D009474:Neurons / Q000378:metabolism* / Q000473:pathology / Q000648:ultrastructure; D017729:Presynaptic Terminals / Q000378:metabolism / Q000473:pathology / Q000648:ultrastructure; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D021381:Protein Transport / Q000235:genetics; D013572:Synaptic Vesicles / Q000378:metabolism* / Q000473:pathology / Q000648:ultrastructure; D022161:Transport Vesicles / Q000378:metabolism / Q000473:pathology / Q000648:ultrastructure
D016189:Dystrophin; D020033:Protein Isoforms