自体嗅黏膜移植修复大鼠脊髓损伤的实验研究

AN EXPERIMENTAL STUDY ON THE TRANSPLANTATION OFAUTOLOGOUS OLFACTORY MUCOSA TO THE INJURED SPINAL CORD IN ADULT RATS

目的 观察自体嗅黏膜植入大鼠脊髓后的变化及其对轴突再生的修复作用。探索临床自体嗅黏膜移植修复脊髓损伤的可能性。 方法 成年雄性Wistar大鼠随机分为嗅黏膜移植组和对照组各 2 0只。嗅黏膜移植组取鼻中隔后部的嗅黏膜组织 (1mm2 )植入自体大鼠脊髓颈 1节段后索内的皮质脊髓束缺损处 (2mm× 1 5mm) ;对照组取鼻腔呼吸区黏膜植入脊髓同样的损伤处。 4～ 6周处死动物 ,移植区冰冻水平切面 ,免疫荧光双标神经丝蛋白 (NF)和神经生长因子受体蛋白 (NGFRp75 ) ,Confocal显微镜下观察 ,另行免疫组织化学染色观察移植嗅黏膜与周围组织的生长情况。 结果 对照组大鼠的损伤处有明显空洞 ,呼吸区黏膜内未见p75染色 ;嗅黏膜移植组可见p75标记的植入的嗅黏膜与周围组织愈合良好 ,空洞明显减少 ,被标记的嗅成鞘细胞向神经组织浸润生长 ,在移植物内有大量被标记的纤细的不分叉的NF纤维穿过。

Objective In order to explore the possibility of autologous transplantation of olfactory mucosa for spinal cord repair,the changes of autologous olfactory mucosa being transplanted into spinal cord and the effect of promoting axon regeneration in adult rats were investigated. Methods Forty male adult rats were divided into two groups randomly:olfactory mucosa transplantation and control groups.Olfactory mucosa (1*!mm+2) was taken from the posterior region of nasal septum,and this graft was transplanted into the posterior funiculus of cervical 1 segment of spinal cord and destructed the corticospinal tract(2*!mm×1^5*!mm).The control graft was derived from the respiratory lamina and then was grafted into the corresponding lesion.After being survived for 4-6 weeks,the animals were killed,the transplanted site was sectioned horizontally,immunofluorescence double labeled with the neurofilament(NF) and anti-NGFR-p75,investigated under the confocal microscope.Another set of slice was used immunohistochemistry to investigate the olfactory mucosa how to integrate with the surrounding tissue. Results The control lesions have the obvious hollow,no p75-positive reaction in the respiratory lamina and no NF-positive fibers grew through it;olfactory mucosa group showed that olfactory mucosa which is labeled p75-positive healed up with surrounded tissue,the hollow declined markedly,the labeled olfactory ensheathing cells(OECs) soakage into the nerve tissue.OECs induced a fine,unbranched,elongative growth of the cut CST axons.The axons were regenerated through the graft and continued to reenter into the caudal host part.Conclusion Autologous olfactory mucosa may be the donor which could repair the spinal cord injury for clinical situations.