Figure 1. Schematic representation of Wallerian degeneration.
A, the cellular organisation of a motoneurone, skeletal muscle fibre and Schwann cells. B, following an axonal lesion, the distal stump of the axon and its motor nerve terminal degenerate. The resident Schwann cells dedifferentiate and proliferate. The axonal, nerve terminal and myelin debris are removed by phagocytosing Schwann cells as well as invading macrophages. The cell body undergoes chromatolysis and the nucleus translocates. C, after the removal of all debris and the formation of bands of Büngner by Schwann cells, the proximal nerve stump regenerates back to the denervated muscle fibre. (Adapted from Nicholls et al. (1992) with permission.)