Evaluation of PRGD/FK506/NGF conduits for peripheral nerve regeneration in rats

Context: Both tacrolimus (FK506) and nerve growth factor (NGF) enhance peripheral nerve regeneration, and in vitro experimental results demonstrate that the combination of FK506 and NGF increased neurite outgrowth compared with either treatment alone. Aim: To determine if the combination of FK506 and NGF benefits peripheral nerve regeneration compared with either treatment alone in vivo. Settings and Design: Rat sciatic nerves were cut off to form a 10 mm defect and repaired with the nerve conduits. All of the 32 Wistar rats were randomly divided into 4 groups: Group A: RGD peptide modification of poly{(lactic acid)-co-[(glycolic acid)-alt-(L-lysine)]} (PRGD)/FK506/ NGF; Group B: PRGD/FK506; Group C: PRGD/NGF; and Group D: autologous nerves. Materials and Methods: At 3 months after surgery, the regenerated rat sciatic nerve was evaluated by electrophysiology, calf triceps wet weight recovery rate, and histologic assessment. Statistical Analysis Used: The SPSS 10.0 software (Bizinsight, Beijing China) was used for statistical analysis. Results: The compound muscle action potentials (CMAPs) of groups A and D were significantly stronger than those of groups B and C. The calf triceps wet weight recovery rate of groups A and D were higher than those of groups B and C. The regenerated nerves of groups A and D were more mature than those of groups B and C. There was no significant difference between groups A and D. Conclusions: PRGD/ FK506/NGF sustained-release nerve conduits are more effective in regenerating nerves than both PRGD/FK506 sustained-release nerve conduits and PRGD/NGF sustained-release nerve conduits. The effect is as good as that of an autograft.