- Distal to an injury axon degenerates (Wallerian degeneration)
- Axon becomes beaded and fragments within a few days
- Phagocytic cells (derived from Schwann cells in PNS, microglia in CNS) remove myelin and
axon fragments.
- Schwann cells and basal lamina remain as tubular structures.
- Nerve injury leads to chromatolysis (loss of Nissl substance from nerve cell body
- Scar tissue forms from Schwann cells and connective tissue
- Schwann cell divide and bridge gap between ends of nerve
- large numbers of new axonal processe emerge from proximal stump
- Schwann cell bridges serve to guide axonal processes
- Sucessful sprouts grow at about 3mm/day
- Remaining Schwann cells guide axons to their destination
- Function restored
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