Effect Of Epidural External Electric Stimulation On Plasticity Of Walking CPG

Objective: To make sure the influence of epidural external electric stimulationon hind limb movement function of spinal cord injury rats，research the relationshipbetween hind limbs motor function change and the expressing of GLUR1andGABABR1in spinal cord tissues，through the correlation analysis to illuminate therelationship between epidural external stimulation on walking function improvementand the CPG plasticity change.Methods:27female SD rats were randomly divided into Sham-operated group,the electric stimulation epidural group and pure spinal cord injury group. Each grouprespectively take one week, two weeks and four weeks time points, respectivelyrecord the hind legs BBB score，nervous electrophysiological examinations，spinalpathology examination and immunohistochemical staining result. By comparing thebehavior change, common peroneal nerve conduction，Gastrocnemiuselectromyogram, pathological changes of spinal cord injury, expression of GLUR1and GABABR1and the number of receptor positive neuron. Observe the influence ofepidural external electric stimulation on hind limb movement function of spinal cordinjury rats，and the relationship between epidural external stimulation on walkingfunction improvement and the CPG plasticity change.Results:1.BBB score in Epidural electric stimulation group is higher than puredamage group rats. By the statistical analysis BBB score in Epidural spinal cordstimulation group around one week, two weeks, and four weeks have differences inthe pure injury group (P <0.05).2. By neural electrophysiological examination resultsthat the common peroneal nerve conduction velocity and compound muscle actionpotential amplitude after epidural electric stimulation were all improved,gastrocnemius electromyogram in spontaneous electrical activity (fibrillationpotentials and positive sharp wave) has no obvious recovery.3. Through pathological found that electrical stimulation group and pure spinal cord injury group nerveregeneration pathological changes does not improve.4. Immunofluorescence stainingresults: expression of GLUR1and GABA BR1significantly decreased after spinalcord injury. Compared with pure damage group, around one week, two weeks, fourweeks, the expression of GLUR1and GABA BR1in Epidural electric stimulationgroup obviously increased.Conclusion:1.Epidural external electric stimulation can obviously improve thefunction of walking in spinal cord injury rat;2. Epidural external electric stimulationto improve the function of rat hind legs walk has no obvious relation with theregeneration of neurons and neural functional recovery；3. Epidural external electricstimulation can improve the expression of the GLUR1and GABABR1in spinal cordinjury rat;4. Excitatory synaptic transmission mediated by GLU is the mainexcitatory activities in Walking CPG,GABA mediated inhibitory synaptictransmission is the key to muscle coordination, speed and rhythmic control, therefore,we hypothesize that electric stimulation improve spinal cord injury rats hind legswalking function related to enhance walking CPG plasticity.