人发角蛋白导管修复周围神经缺损的实验研究

目的探索用人发角蛋白（HHK）制成的导管对大段缺损的周围神经的修复效果。方法将25只新西兰兔分成3组,对照组不接受手术;另2组切除胫神经10mm,分别用缝合线（无HHK组）和HHK导管（HHK组）连接神经两断端,术后不同时间分别进行神经电生理检查、解剖和组织学观察。结果术后92d经电生理检查,HHK组较无HHK组功能恢复快。解剖观察发现,神经两断端之间以及HHK导管的腔隙被白色新生组织充满,人发部分消失,残余的人发易脆易断。在光镜下可见人发周围大量再生的雪旺细胞和较幼稚的神经纤维,神经纤维无序排列,人发被初步降解。术后1年,人发被完全降解,神经缺损部位修复完好。结论 HHK导管可诱导神经纤维再生,跨过10mm的缺损间隙,从而修复神经缺损。HHK是制作神经导管的较为理想的材料。

Experimental study of repairing peripheral nerve damage with conduit made of human hair keratin

Objective To evaluate the effect of conduits made of human hair keratin (HHK) in repairing injured peripheral nerve. Methods Twenty-five normal New Zealand rabbits were used in this study, which were divided into 3 groups including a control group (n=5) and 2 experiment groups. The tibial nerves of rabbits in the 2 experiments groups were transected to create a 10-mm gap, then were either routinely sutured (group II, n=10) or repaired by inserting both nerve stumps into the lumen of the conduit, followed by suturing the epineurium of the nerve stumps with HHK conduits using 9-0 nylon (group III, n=10). Electrophysiological, anatomic and histological examinations were performed at different time points after surgery. Results Noteworthy improvement in healing could be seen from electrophysiological results of group III, in which HHK conduits were partially degraded and embedded in white tissue, crisp and fragile. Large amount of infantile myelinated nerve fibers and schwann cells were observed under optical microscope to regenerate around HHK, which was partially degraded and absorbed, 92 dpostoperatively. One year after the operation, the severed tibial nerves were perfectly repaired and HHK completely degraded. Transmission electron microscopy identified Schwann cell proliferation and myelinization around HHK 92 d after operation, but the delamination of the myelin was not manifest until observed with greater magnifications. There were nerve fibrils in the myelin, where organelles such as mitochondrion could be seen. Conclusion As an ideal material for nerve injury repair, HHK conduits can guide tibial nerve elongation across a 10-mm gap.