Diseases of the Neuromuscular Junction. Degenerative morphological alterations in neuromuscular junctions (NMJs) in wild-type and Sod1−/− muscles.NMJs in EDL and gastrocnemius muscles were visualized via Thy1-YFP fluorescence in the presynaptic axon and nerve terminal (green), as described in detail in Materials and Methods, and by staining acetylcholine receptors (nAChRs) with fluorophore conjugated α-bungarotoxin (red). Partially innervated and completely denervated NMJs in Sod1−/− muscle were indicated (arrows). Axon thinning was also frequently observed in Sod1−/− mice (arrow heads). Scale bars: 50µm. The lack of CuZnSOD leads to impaired neurotransmitter release, neuromuscular junction destabilization and reduced muscle strength in mice: Shi Y, Ivannikov MV, Walsh ME, Liu Y, Zhang Y, Jaramillo CA, Macleod GT, Van Remmen H - PloS one (2014). Not altered. CC.