ABSTRACT
Based on the previous work of other researchers, we first removed 1 cm of the spinal
cord of rats and grafted the gap with peripheral nerve. We obtained progression of
regenerating axons inside the grafts, but regrowing axons halted at the distal cord
level. We then tried directly to connect the cephalad stump of the cord with the sciatic
nerve, several surgical models of which have been previously studied. The latest model
uses a homologous sciatic nerve of an inbred Wistar rat, to bridge the gap between
the lateral bundle of the cord, proximal to the origin of the sciatic roots, and the
sciatic trunk distal to the fusion of its roots. Good re-innervation of the sciatic
nerve and distal muscles was found. It was demonstrated by: a) the remyelination of
regenerated nerve fibers, not only in the grafts but also in the sciatic nerve; b)
re-innervation of motor endplates; and c) clinical and electromyographic muscle responses.
Central nervous system (CNS) neurons are able to regenerate not only their axons through
the CNS but also into peripheral nerves. The capacity of CNS neurons to neurotize
peripheral nerves reaching terminal organs, is a basic finding.
Many questions arise from the study, including: Can these results be extrapolated
to humans? What would be the function of these regenerated fibers that might lack
some of the control mechanisms peculiar to peripheral nerves?
