Juvenile neuroaxonal dystrophy in a Rottweiler: accumulation of synaptic proteins in dystrophic axons.

Dystrophic axons in a 2-year-old male Rottweiler with neuroaxonal dystrophy have shown synaptophysin, synapsin-I, synaptosomal-associated protein of 25 kDa (SNAP-25), Rab 3a, and alpha-synuclein immunoreactivity. Similar findings have been observed in isolated dystrophic axons in the nuclei gracillis and cunneatus in five dogs aged between 14 and 18 years. Abnormal expression of integral synaptic vesicle, synaptic vesicle-associated presynaptic plasma membrane and cytosolic proteins, which participate in the trafficking, docking and fusion of the synaptic vesicle to the plasma membrane, suggest severe disruption of axonal transport in dystrophic axons in canine neuroaxonal dystrophy.