Department of Hand Surgery, University Hospital, Malmö, Sweden.
Restor Neurol Neurosci. 1996 Jan 1;9(3):141-9. doi: 10.3233/RNN-1996-9302.
The effects of granulation tissue exposure on regeneration of sensory axons after a test crush lesion in rat sciatic nerves were studied. Chromic catgut threads were applied subcutaneously in the back of rats. Three weeks later the surrounding granulation tissue was isolated and transposed to the sciatic or tibial nerve in the same rat. Immunocytochemical, light and electron microscopic evaluation of the isolated granulation tissue revealed numerous EDI and ED2 positive macrophages. After an additional three weeks the sciatic nerves were crushed and the axonal outgrowth lengths were measured by the pinch reflex test and by neurofilament staining 3 or 6 days later. The regeneration distances in the sciatic nerve exposed to granulation tissue were significantly longer compared with that of nerves to which only subcutaneous tissue was transposed. Thus, the nerve had become conditioned by the transposure of macrophage rich tissue. After the transposure macrophages were present close to the nerve at the time point of the test crush lesion, but no signs of degeneration or inflammation in the endoneurial space were observed. It was also found that the outgrowth lengths in the tibial nerve branch were consistently longer than in the peroneal branch of the sciatic nerve. It is concluded that granulation tissue, containing macrophages, can induce a conditioning effect in the sciatic nerve. We suggest that this effect is related to factors emanating from macrophages in the transposed tissue.
研究了肉芽组织暴露对大鼠坐骨神经试验性压榨损伤后感觉轴突再生的影响。铬制肠线皮下应用于大鼠背部。3 周后，将周围的肉芽组织分离并转移到同一只大鼠的坐骨神经或胫神经中。对分离的肉芽组织进行免疫细胞化学、光镜和电镜评估，显示有大量 EDI 和 ED2 阳性巨噬细胞。另外 3 周后，对坐骨神经进行压榨，并通过夹捏反射试验和神经丝染色在 3 或 6 天后测量轴突的生长长度。暴露于肉芽组织的坐骨神经的再生距离明显长于仅转移皮下组织的神经。因此，神经通过富含巨噬细胞的组织转移而得到调节。转移后，巨噬细胞在试验性压榨损伤时靠近神经，但在内神经鞘空间没有观察到退行性或炎症迹象。还发现，胫神经分支的生长长度始终长于坐骨神经的腓神经分支。结论是，含有巨噬细胞的肉芽组织可以在坐骨神经中诱导一种调节作用。我们认为这种作用与转移组织中巨噬细胞产生的因素有关。
