ABSTRACT
Apolipoprotein E (apo E) is thought to mediate the reutilization of myelin cholesterol
for nerve regeneration. Prior research suggests that apo E is not essential for nerve
regeneration following a nerve crush injury. This study was conducted to determine
if apo E is essential for nerve regeneration after nerve transection and interposition
nerve autograft. Nerve regeneration of transgenic apo E-deficient mice was compared
with control mice after a sciatic nerve neurolysis and repair and interposition autograft.
Histomorphometric assessment and histology were performed on distal nerve segments
to evaluate nerve regeneration. Apo E-deficient mice demonstrated no difference in
total fiber number or nerve fiber width when compared with controls; however, the
nerve fiber density and percent neural tissue of apo E-deficient mice were significantly
less than controls following nerve repair. Apo E deficiency does not affect nerve
regeneration. It is likely that the low nerve fiber density and the low percent neural
tissue associated with apo E-deficiency result from impairment in the disposal of
myelin debris.
KEYWORDS
Peripheral nerve regeneration - Apolipoprotein E - myelin lipids
