关键词: 腰椎间盘突出症, 椎间盘, 神经生长因子受体, 腰痛, 神经生长因子

Abstract: ［Abstract］ Objective To investigate the expression of nerve growth factor（NGF）and its receptor, tyrosine kinase A（TrkA）and p75 neurotrophin receptor（p75NTR）in discs from patients with lumbar disc herniation（LDH）and the effect of NGF on clinical symptoms. Methods Patients（n=62）with a singlelevel lumbar disc herniation treated by surgery were included, disc samples were obtained from patients during surgery. The expression of NGF, TrkA and P75NTR was detected by immunohistochemistry method. Protein levels were quantified using an enzyme?linked immunosorbent assay（ELISA）for NGF. Levels of NGF in the discs were compared between low?grade and high?grade degenerated discs. Multiple linear regression analysis was used to assess the factors affected to NGF level. Patient′s symptoms were assessed using a visual analog scale（VAS）and the Oswestry disability index（ODI）；the influence of NGF levels on preand postoperative symptoms was examined. Results Immunopositive staining for NGF, TrkA and P75NTR was identified in the chondrocyte?like cells of the disc tissue. No significant differences in levels of NGF were found between low?grade and high?grade degenerated discs. The results of multiple linear regress analysis showed the cellular immunopositivity of NGF and TrkA are significantly related to NGF levels. Pre?operative symptoms were not related to NGF levels. Post?operative lower extremity pain and low back pain（LBP）were greater in patients with high levels of NGF. Conclusion This study demonstrates that NGF and its receptor, TrkA and P75 were expressed by disc cells and NGF is actually being produced by the chondrocyte?like cells of the disc tissue. Our results showed that pre?operative disc protein levels of NGF affected postoperative LBP and lower extremity pain, suggesting there is some degree of impact of NGF on generation of LBP and lower extremity pain.

Key words: lumbar disc herniation, lumbar intervertebral disc, neurotrophin receptor, nerve growth factor, low back pain