Target Organs Electrical Stimulation Promote Peripheral Nerve Regeneration And Functional Recovery In Rat

Aim:The incidence of peripheral nerve injury(PNI) is increasing trend year by year,the nerve repair process after PNI is extremely complex and the effect of target organ cannot be ignored in the repair process. To explore the role of target organs after peripheral nerve injury(PNI), and electrical stimulation target organs to promote nerve regeneration and its mechanism, we detect the amount of regenerated nerve and maturity of myelin, and neuromuscular motor and sensory function recovery, from neuromuscular morphology, function and behavior of animal to evaluate the effect of repair of peripheral nerve injury.Methods:1, First of all, we adopted the sciatic nerve injury model, and implemented the electrical stimulation treatment(1 h/d, 100 ms and 100μA, 2w). Postoperative 8w,,we detected electrical stimulation to decrease muscle atrophy by calculate gastrocnemius wet weight ratio, gastrocnemius force test, HE-staining, acetylcholine quantity and the expression of MRFs protein;2, Then, we cultured L6 cell in vitro and electrical stimulate skeletal muscle cells,and then observed the change of MRFs m RNA level, discussed the mechanism of electrical stimulation.3, Afterwards, we detected distal regenerate nerve immunofluorescence staining and toluidine blue staining, electron microscope, nerve electrophysiology, footprint gait analysis and other methods, from morphology to behavior; we analyzed the electrical stimulation how to slow down the effect of muscle atrophy, and then further tested target organ affect regeneration nerve repair and recovery and its mechanism;4, Moreover, we used the femoral nerve damage model, also implemented the same electrical stimulation treatment, postoperative 8 w, we observed regeneratednerve repair and motor neuron selective regeneration, as well as the effect of target organs function recovery by analyzing footprint gaits and reverse tracing method.5, Finally, we observed the expression of neurotrophic factors m RNA level in the regenerated distal nerve and the mechanism of target organs ES.Results:1, Rat sciatic nerve injury model, detection of wet weight ratio and strength of the gastrocnemius muscle, electrical stimulation group were greater than the control group; HE staining results showed that the average area of muscle fiber in electrical stimulation group was greater than the control group; acetylcholine receptor number per unit area of electrical stimulation group were much more(P < 0.05; vs. Ctrl).Electrical stimulate up-regulated the expression of MRFs protein level and the m RNA level in the muscle cells(P < 0.05; vs. Ctrl). Electrical stimulation is effective to slow denervation muscle atrophy.2, The far side of the regenerated nerve immunofluorescence and toluidine blue staining showed that the regeneration of nerve fibers in ES group number significantly more than the control group; And electronic microscope results showed that the regeneration of nerve myelin maturity ES group better(the number of regenerated nerve, axon diameter, the thickness of myelin sheath and G value ratio)(P < 0.05; vs. Ctrl).3, At the same time, the femoral nerve model, the electrical stimulation treatment significantly increased the number of the regeneration of neurons and motor neurons of the correct projection ratio(P < 0.05; vs. Ctrl). Further, we analyzed compound muscle action potential(CMAP), nerve action potential(NAP) and the sciatic nerve function index(SFI) at the 8 weeks in sciatic nerve injury model. All of the data proved that electrical stimulation treatment effect is remarkable. In regeneration of nerve, the expression of nerve cell adhesion factor(NCAM) and neurotrophic factor(NTF) in protein and m RNA levels increased(P < 0.05; vs. Ctrl).Conclusions:We concluded that the treatment of target organs electrical stimulation of peripheral nerve injury decrease denervation muscle atrophy effectively, and isbenefited to promote peripheral nerve regeneration and motor neuron selective regeneration; and availably improve neuromuscular function recovery; the expression of NCAM and NTFs in m RNA levels increased.