高分子神经导管的理化特性对周围神经再生影响的研究

Effects of physical and chemical properties of polymeric nerve conduit on peripheral neuranage-nesis

目的 :评估高分子材料导管的降解时间和通透性对修复外周神经缺损的影响。方法 :利用四种通透性和降解时间不同的聚酯 -聚碳酸酯神经桥接导管 ,桥接 SD大鼠右后肢坐骨神经大于 10 mm缺损 ,并与未套管的神经缺损大鼠相对照。术后定期观察大鼠的肢体情况 ;在 4、12、2 0周时 ,电生理测定再生神经支配的胫前肌收缩情况 ,大体及普通光镜水平下 ,观察各实验组和对照组神经再生和神经导管在体内的降解情况。结果 :体内导管的降解时间 :A型 12周 ,B和 C型约 4周 ,D型约 2 0周。A组再生神经纤维组织学优于其他实验组和对照组 ,平均秩次为5 3.17、38.83、2 6 .6 0、4 9.17、2 0 .2 3(P<0 .0 0 5 ) ,导管周围炎症程度重于 B、C组和对照组 ,但较 D组为轻 ,平均秩次为 4 5 .87、36 .2 7、34.83、5 1.6 3、2 1.4 (P=0 .0 0 1)。再生神经支配胫前肌电刺激收缩阳性率依次为 A组 93.33%、B组 6 0 %、C组 2 0 %、D组 73.33% ,差别有显著性意义 (P<0 .0 0 5 )。结论 :具有较好通透性和适宜降解时间的高分子材料神经导管 。

Objective: To evaluate the effects of degradation time and permeability of polymeric conduits on nerve regeneration. Methods: After establishment of rat models with over 10 mm gap of sciatic nerve in right hind legs,four kinds of poly (ester,carbonate) nerve conduits was used to bridge the gaps and one group without conduit in gaps was used as control. The nerve regeneration and conduit degradation were examined both macroscopically and microscopically. The contraction of the muscle controlled by regenerated nerve was measured electrophysiologically at 4,12 and 20 weeks after the operation. Results: Biodegradation time of nerve conduits in vivo was as fellows: 12 weeks in group A,4 weeks in group B and group C,and 20 weeks in group D,respectively. The histological quality of regenerative sciatic neurofibra in group A was the best among all groups (Mean rank:53.17,38.83,26.60,49.17 and 20.23,P<0.005),but the inflammatory reaction in group A was only less than that in group D and more than that in the other groups (Mean rank:45.87,36.27,34.83,51.63 and 21.4,P=0.001). The responsive rates of (tibialis) anterior muscle for electric stimulation in group A,B,C and D were 93.33%,60%,20% and 73.33%,respectively(P<0.005). Conclusion: Absorbable conduits with relatively good permeability and appropriate middle degrade time improve nerve regeneration and renovate function.