慢性压迫性脊髓损伤后神经前体细胞的增殖情况

目的　通过分析成年大鼠慢性压迫性脊髓损伤后及减压后巢蛋白表达的变化 ,探讨神经前体细胞的增殖。　方法　选用健康Wistar大鼠 5 0只 ,体重 2 80～ 32 0g。制备慢性压迫性脊髓中度、重度损伤及重度压迫损伤减压后 3,10d模型 ,自距压迫边缘至 5mm段脊髓组织切片。正常成年健康大鼠作为正常对照组。巢蛋白、胶质纤维酸性蛋白采用免疫组织化学染色 ,计算机图像分析仪定量分析 ,观察神经前体细胞的增殖情况。　结果　成年大鼠慢性压迫性脊髓中、重度损伤及重度压迫损伤减压后 3d ,巢蛋白在白质、灰质及脊髓中央管的室管膜细胞和减压后 10d组白质中均有明显表达 (P <0 .0 5 ) ,以重度压迫组最为显著 (P <0 .0 1)。减压后 10d组灰质与正常对照组比较 ,差异无显著性意义 (P >0 .0 5 )。与正常对照组相比 ,各损伤组脊髓内胶质纤维酸性蛋白表达增强 ;胶质纤维酸性蛋白阳性细胞数目增多 ,胞体肥大 ,突起增粗、增长。　结论　成年大鼠慢性压迫性脊髓损伤及减压后早期存在神经前体细胞增殖。星形胶质细胞参与神经前体细胞的增殖与迁移 ,对脊髓具有重要的营养修复作用。

Regeneration of the neural precursor cells after chronic compressive spinal cord injury in adult rats

Objective To investigate the regeneration of the neural precursor cells after chronic compressive spinal cord injury in adult rats through analysis of the espression changes of nestin. Methods Wistar rats ( n =50) weighing 280-320 g were drilled at the root of spinous process of T 12 . The models of moderate and severe compressive spinal cord injury as well as models at days 3 and 10 after decompression of severe compressive spinal cord injury were made. The normal adult rats were used as control group. The slices of spinal cord tissues 5 mm from the edge of compression margin were used to observe the proliferation of neural precursor cells through immunohistochemical stain of nestin and glial fibriallary acidic protein (GFA P ) as well as quantitative computer image analysis. Results Three days after decompression of moderate injury,severe injury and severe compressive injury,nestin was expressed significantly white matter,grey matter and ependymal cells of the central canal as well as in the white matter of group 10 days after decompression ( P <0.05). The nestin expressed the most significantly in the severe compression group ( P <0.01). Compared with normal rats,glial fibriallary acidic protein (GFAP) expressed more intensively in all groups and the positive cell number of GFAP was increased,with cytoplasmic hypertrophy,lumpy and longer processes. Conclusions Regeneration and migration of the neural precursor cells exist in chronic compressive spinal cord injury and early after compression. The astrocytes participate in proliferation and translocation of the neural precursor cells and have an important restorative and nutritional effects on the spinal cord.