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Objective: To study the use of PLGA nerve conduits constructed new three-dimensional rat peripheral nerve defect repair feasibility of nerve conduit microfilaments support role and a different number of filaments of nerve regeneration, as the ultimate development of the ideal artificial neural provide theoretical and experimental evidence. Methods: materials using new three-dimensional nerve conduit polylactic acid-glycolic acid copolymer (PLGA, 85:15), first prepared as a material which can absorb a porous wall, which contains a number of different three-dimensional tubular structure stent filaments; then completely randomly 40 adult SD rats were divided into four groups, each 10 to prepare a rat sciatic nerve defect model of 12mm, 12mm with the conduit bridging sciatic nerve defect in rats. Group A: PLGA nerve conduits group; B group: PLGA nerve catheter placed 20 PLGA longitudinal filaments; C group: PLGA nerve catheter placed 40 PLGA longitudinal filaments; D Group: nerve autograft group. A, B, C of each group were injected nerve catheter NGF laminin mixture 0.3ml. All rats as experimental side left hind, right hind limb as the control side. Postoperative dynamic rat muscle atrophy and limp, etc., measured 12 weeks after stent filaments containing different amounts of nerve regeneration conduit motor nerve conduction velocity, triceps wet weight recovery rate. On the regenerated nerve in 1/3 histological observation and image analysis to evaluate the effects of nerve repair, and with autologous nerve graft compared. Results: After 12 weeks, the rats operated side plantar ulcer healing and pain already, but the A group and C group were relatively slow reaction; B and D groups Muscle atrophy has been restored, lameness reduced, group A and group C showed no recovery; each group were regenerated nerve ingrowth through the distal nerve conduit, B, D group compared with regenerated nerve A, C group thick, PLGA nerve conduits and microfilaments are basic degradation; regeneration motor nerve conduction velocity in group B and D were significantly faster than in group A and group C (P <0.05); A group, C group most obvious muscle atrophy, while the B group, D group muscle atrophy and muscle atrophy lesser extent basic rather, the difference was not statistically significant (P> 0.05); regenerated nerve in 1/3 light and electron microscopy, A group, C group and B group, D group sparse nerve fibers, smaller axons, myelin than thin, immature, and group C edema, loose structure of myelin within the filaments and microtubules than Blur: The B and D groups coarse axon, myelin sheath thickness, more mature, myelin within the micro- filaments and microtubules clear and neat. Pathological image analysis nerve fiber counts up to D group, B group, followed by nerve fiber diameter, axon diameter and myelin thickness in group B compared with group D showed no significant difference (P> 0.05), while in group A, C group differences were statistically significant (P <0.05), B group and D group and the number of regenerated nerve fibers were much better than the maturity of the A and C groups. Conclusions: 1. Developed new three-dimensional PLGA nerve conduits can effectively guide the SD rat sciatic nerve regeneration and nerve gap longer than 12mm is an ideal nerve conduit; 2. Nerve catheter stent filaments can effectively guide nerve regeneration, The number of filaments of nerve regeneration to a certain extent, but may inhibit the excessive number of nerve regeneration.
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