Axotomy-dependent and -independent synapse elimination in organ cultures of Wld(s) mutant mouse skeletal muscle.

Progressive "dying back" neurodegenerative diseases are debilitating due to loss of connectivity after nerve terminal and axonal withdrawal, which impairs peripheral nerve function and leads ultimately to neuronal cell death. The mutant mouse (Wallerian degeneration slow; Wld(s)) provides an accessible model system to understand orthograde and retrograde degeneration, because in these mice axotomy induces slow, progressive withdrawal of nerve terminals from motor endplates. Axon degeneration itself is about 10 times slower than in wild-type mice.