Article

Functional outcomes are generally poor following peripheral nerve
injury (PNI). The reason is multifactorial but includes the misdirection of
regenerating axons to inappropriate end organs.
It has been shown that brief
electrical stimulation (Estim) of nerves has the potential to improve the
accuracy and rate of peripheral axon regeneration. The present study
explores a novel percutaneous transvertebral approach to Estim, which was tested
in the mouse femoral nerve model. METHODS: Inspired by the protocol of Gordon and
colleagues (ie, 20 Hz, for 1 hour), we applied Estim to the cervicothoracic
spinal cord (SC-Estim) to remotely activate lumbar motor neurons following
transection and repair of the femoral nerve. Fluorescent dyes were applied to the
distal nerve to label reinnervating cells. Sections of nerve were taken to
quantify the numbers of reinnervating axons as well as to stain for a known
femoral axon guidance molecule-polysialylated neural cell adhesion molecule
(PSA-NCAM). RESULTS: In comparison to sham treatment, SC-Estim led to
significantly greater expression of PSA-NCAM as well as improved the specificity
of motor reinnervation. Interestingly, although SC-Estim did not alter the number
of early reinnervating (ie, pioneer) axons, there was a reduction in the number
of retrogradely labeled neurons at 2 weeks postrepair. However, by 6 weeks
postrepair, there was no difference in the number of neurons that had
reinnervated the femoral nerve. CONCLUSIONS: The present findings support the
development of SC-Estim as a novel approach to enhance the specificity of
reinnervation and potentially improve functional outcomes following PNI.

Langue : ANGLAIS