Pathological and immunohistochemical study on nerve injury by disc herniation

本研究的目的是评估椎间盘突出后脊神经根周围的机械因素和/或免疫组织化学反应。采用日本大白兔制作腰椎间盘病变实验动物模型，将正常椎间盘材料或退变椎间盘材料放置在脊髓根上，并进行或不进行进一步的机械压迫。作为对照研究，脂肪组织的放置也被用于对侧脊神经根。采用多种抗兔单克隆抗体对脊髓神经根或邻近椎间盘材料进行病理或免疫组化观察。此外，用hoeseradish过氧化物酶评价脊神经根的轴突血流。在未进一步机械压迫的情况下，脊髓根未见免疫组织化学或病理异常。机械压迫脊神经根时，轴突血流受到影响。神经根周围巨噬细胞的出现是可变的，在正常椎间盘材料放置的脊髓神经根中CD4或CD5染色明显。这些结果表明椎间盘突出引起的神经损伤与机械压迫密切相关，椎间盘退变对神经组织的影响比正常椎间盘材料的影响小。

The purpose of this study is to evaluate mechanical factor and/or immunohistochemical reaction around the spinal nerve roots by disc herniation. Experimental animal model for lumbar disc lesion was made using Japanese white rabbits and placement of normal disc material or degenerated disc material on the spinal root with or without further mechanical compression. Placement of fatty tissue also was used at the counterlateral spinal nerve root as a contrast study. The spinal nerve roots or adjacent disc material was studied on pathological or immunohistochemical appearance using various antirabbit monoclonal antibodies. Furthermore, axonal flow with hoeseradish peroxidase was evaluated for the spinal nerve roots. No immunohistochemical or pathological abnormality was noted in the spinal roots without further mechanical compression. Axonal flow was involved in the spinal nerve roots with mechanical compression. Emergence of macrophages around the nerve roots was variable and stain of CD4 or CD5 was prominent in the spinal nerve roots with placement of normal disc material. Those findings indicated that nerve injury by disc herniation is strongly related to mechanical compression and degenerated disc is less influencing on nerve tissue rather than normal disc material.