On the other hand, in some neurons, after severance of the axon from the rest of the cell (spinal motor cell), the whole nerve cell as well as the severed axon degenerates, and may eventually die and be removed.
In the severed axon the degeneration is first evident in a breaking down of the naked nerve filaments of the motor end plate.
A little later the breaking down of the whole axon, both axis cylinder and myelin sheath alike, seems to occur simultaneously throughout its entire length distal to the place of severance.
This indicates that the conjunction between the conducting substance of the dendrons and that of the axon can be effected without the intermediation of the cell body.
The neuron is described as having a cell body or perikaryon from which the cell branches - dendrites and axon - extend, and it is this perikaryon which, as its name implies, muscle produces lactic acids during activity, it has been suggested that acids are among the "fatigue substances" with which muscle poisons itself when deprived of circulating blood.