ABSTRACT
An experimental study was conducted using rat soleus muscles to characterize reinnervation
of the denervated muscles by direct muscle neurotization. Also studied was whether
there is any difference in the regeneration process between original (tibial) and
foreign (peroneal) nerve neurotization. For functional evaluation, an electrophysiologic
study was carried out by analyzing pattern, latency, amplitude, and duration of compound
motor action potential. In a histochemical study, both hematoxylin-eosin stain and
nicotineamide adenin dehydrogenase stain were used to identify the morphology and
the change in the type of muscle fiber. Combined silver-acetylcholinesterase stain
was utilized to identify reinnervated motor endplates and axonal sprouting. Evidence
of regeneration of the denervated muscle by direct muscle neurotization could be confirmed.
Regenerating muscles showed type grouping of muscle fibers. The newly-formed ectopic
motor endplate was connected with axonal sprouting. The giant motor endplate composed
of mature axon sprouting and several new ectopic motor endplates appeared in the neurotization
group. There was no specific difference in the regeneration process between original
and foreign nerve neurotization.
