Chitosan/polylactic acid complex for repair of peripheral nerve defects / 中国组织工程研究

ABSTRACT

BACKGROUND:The mechanical strength of nerve conduits made by chitosan is poor and easy to col apse, which is not conducive to the nerve regeneration. OBJECTIVE:To explore the feasibility of chitosan/polylactic acid complex in the repair of peripheral nerve defects in rats. METHODS:Thirty Sprague-Dawley rats were enrol ed to establish models of unilateral sciatic nerve defects, and then randomly divided into three groupsautologous nerve, silicone catheter and chitosan/polylactic acid complex were used for defect repair in the three groups, respectively. At 12 weeks after operation, appearance of bridged nerves, surface adhesion, formation of neuroma were observed;nerve conduction velocity, action potential amplitude and latent period were determined;hematoxylin-eosin staining was performed to observe the number of regenerated axons and area of regenerated nerves;wet weight of the complete triceps surae was measured. RESULTS AND CONCLUSION:At 12 weeks after repair, the regenerated nerves in the three groups al passed through the 5 mm nerve defect gaps, and neuroma only formed in the silicone catheter group. The diameter of regenerated nerves in the three groups was ranked as fol owsautologous nerve group>chitosan/polylactic acid group>silicone catheter group (P<0.05). High-density regenerated axons neatly arranged in the autologous nerve and chitosan/polylactic acid groups, and the number of regenerated axons was higher than that in the silicone catheter group (P<0.05). Moreover, the nerve conduction velocity, action potential amplitude and wet weight of the complete triceps surae were significantly higher in the autologous nerve and chitosan/polylactic acid groups than in the silicone catheter group (P<0.05), but the latent period was lower than that in the silicone catheter group (P<0.05). These findings indicate that the chitosan/polylactic acid conduits can promote peripheral nerve regeneration.