Regeneration
Regeneration follows degeneration. Regeneration is rapid in PNS, allowing for rates of up to 1 millimeter a day of regrowth. Grafts may also be needed to allow for appropriate reinnervation. It is supported by Schwann cells through growth factors release. CNS regeneration is much slower, and is almost absent in most species. The primary cause for this could be the delay in clearing up myelin debris. Myelin debris, present in CNS or PNS, contains several inhibitory factors. The elongated presence of myelin debris in CNS could possibly hinder the regeneration. An experiment conducted on Newts, animals that have fast CNS axon regeneration capabilities, found that Wallerian degeneration of an optic nerve injury took up to 10 to 14 days on average, further suggesting that slow clearance inhibits regeneration.
Read more about this topic: Wallerian Degeneration
Famous quotes containing the word regeneration:
“The republic, as I at least understand it, means association, of which liberty is only an element, a necessary antecedent. It means association, a new philosophy of life, a divine Ideal that shall move the world, the only means of regeneration vouchsafed to the human race.”
—Giuseppe Mazzini (1805–1872)
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—Joseph Campbell (1904–1987)