P(LLA-CL) nerve conduits of electrospun nanofibers for repair of sciatic nerve defect in rats

Abstract

Objective To investigate the effects of P(LLA-CL) nerve conduits of electrospun nanofibers in repairing sciatic nerve defect in rats. Methods Fifty-four rats were randomly divided into three groups,with eighteen rats in each group. A 15 mm defect in the left sciatic nerve was created in the rats and was repaired with P (LLA-CL) conduits ( group A), with silicon conduits ( group B), and with autografts ( group C),respectively. Nerve regeneration was evaluated with gross observation, SFI (Sciatic Functional Index),neuroelectrophysiological examination, muscle weight, neuromorphometry and electron microscopy at 4 weeks,8weeks and 12 weeks after the operation. Results Regenerating axons reached mid-tube level in group A 4 weeks after the surgery. At 8 weeks the regenerating fibers had traversed the entire length of the conduit although the nerve fibers were thin. At 12 weeks the regenerated nerve fibers were much thicker and less adhesive. SFI,electrophysiological evaluation, wet weight of gastrocnemius and soleus muscles, and neuromorphometry in group A were slightly inferior to those of group C but significantly better than those of group B. Conclusion PLLACL nerve conduits of eleetrospun nanofibers can effectively promote nerve regeneration of rat sciatic nerve. They can potentially be used as a substitute for autogafts to repair nerve defects. Key words: Peripheral nerves; Nerve regeneration; Animal experimentation; Poly(L-lactide-coepsilon-caprolactone)