Changes Of Agrin Expression In The Somatic Motor Neurons Of Cornu Anterius Medullae Spinalis After Their Axon Regeneration Into Automatic Nerves

Objective To study the changes of agrin expression in spinal cord motor neurons after somatic-autonomic ventral root (VR) anastomosis and somatic - somatic VR anastomosis, and the factors related to the synapse formation of foreign nerve regeneration. Methods The artifical somatic-automomic reflex pathway and somatic nerve self-anastomsis were established in rats. Retrograde tracing was carried out to label the motor neurons, and the neurons were isolated by flow cytometry. Real-time PCR was used to investigate the agrin mRNA expression of the neurons. Anterograde tracing and immunofluorescence technique were carried out to label the new synapses of pelvic ganglia (PG). Results After 4 months of surgery, the motor axon regenerated into PG succsessfully and formated the new synapses. The neurons involved in foreign nerve regeneration can be isolated successfully by retrograde tracing and flow cytometry. The expression of agrin in L4-L6 VRs anastomosis group was lower than control group of L4-L4 VR self-anastomosis (P<0.05) and normal group (P <0.05) Conclusion The somatic motor axon could regenerate into PG and fomate new synapses. The differences of agrin expression between somatic-autonomic and somatic-somatic nerve regeneration may be related to the changes of target organ.