Abstract: Objective To explore the effect of peripheral nerve electrical stimulation on axon regeneration after spinal cord injury (SCI) in rats. Methods Nighty-two healthy Sprague-Dawley rats were randomly divided into blank control group (n=12), control group (n=40) and experimental group (n=40). All groups were suffered NYU impaction to prepare T8 SCI models, the control group and the experimental group implanted stimulating electrode on the sciatica nerve. The experimental group received electric intervention in addition. They were evaluated with BBB score one day, one week, two weeks, four weeks and eight weeks after modeling; and with motor evoked potentials (MEP) one week, two weeks, four weeks and eight weeks after modeling. Morphological changes and the expression of neurofilament protein (NF)-200 and glial fibers acid protein (GFAP) were observed by HE staining and immunohistochemistry one week, two weeks, four weeks and eight weeks after modeling. Results There was no significant difference in BBB scores among three groups (P>0.05) in all the time points except eight weeks (P<0.05). There was no significant difference in the amplitudes and latencies among three groups one week after modeling (P>0.05), however, there was significant difference two weeks, four weeks and eight weeks after modeling (P<0.05). All the groups showed syringomyelia and glial scar formation one week, two weeks, four weeks and eight weeks after modeling. There was no significant difference in NF-200 axon count among three groups one week after modeling (P>0.05), but was different two weeks, four weeks and eight weeks after modeling (P<0.05). There was no significant difference in GFAP area count among three groups in all the time points (P>0.05). Conclusion Implantable peripheral nerve electrical stimulation can improve conduction function and motor function in rats with SCI. And it may promote axonal regeneration of the injured segments.

Key words: spinal cord injury, electrical stimulation, axonal regeneration, rats