title: Increase of nerve growth factor levels in the human herniated intervertebral disc: can annular rupture trigger discogenic back pain?
abstract: BACKGROUND
  Nerve growth factor (NGF) has an important role in the generation of discogenic pain. We hypothesized that annular rupture is a trigger for discogenic pain through the action of NGF. In this study, the protein levels of NGF in discs from patients with disc herniation were examined and compared with those from discs of patients with other lumbar degenerative disc diseases.
  
  
  METHODS
  Patients (n = 55) with lumbar degenerative disc disease treated by surgery were included. Nucleus pulposus tissue (or herniated disc tissue) was surgically removed and homogenized; protein levels were quantified using an enzyme-linked immunosorbent assay (ELISA) for NGF. Levels of NGF in the discs were compared between 1) patients with herniated discs (herniated group) and those with other lumbar degenerative disc diseases (non-herniated group), and 2) low-grade and high-grade degenerated discs. Patient's symptoms were assessed using a visual analog scale (VAS) and the Oswestry disability index (ODI); the influence of NGF levels on pre- and post-operative symptoms was examined.
  
  
  RESULTS
  Mean levels of NGF in discs of patients were significantly higher in herniated discs (83.4 pg/mg total protein) than those in non-herniated discs (68.4 pg/mg).
  
  
  CONCLUSIONS
  This study reports that NGF increased in herniated discs, and may play an important role in the generation of discogenic pain. Analysis of patient symptoms revealed that pre-operative NGF levels were related to post-operative residual lower extremity pain and LBP in motion. The results suggest that NGF in the disc is related to pain generation, however, the impact of NGF on generation of LBP varies in individual patients.
authors: Yasuchika
authors: Y
authors: Aoki
authors: Arata
authors: A
authors: Nakajima
authors: Seiji
authors: S
authors: Ohtori
authors: Hiroshi
authors: H
authors: Takahashi
authors: Fusako
authors: F
authors: Watanabe
authors: Masato
authors: M
authors: Sonobe
authors: Fumiaki
authors: F
authors: Terajima
authors: Masahiko
authors: M
authors: Saito
authors: Kazuhisa
authors: K
authors: Takahashi
authors: Tomoaki
authors: T
authors: Toyone
authors: Atsuya
authors: A
authors: Watanabe
authors: Takayuki
authors: T
authors: Nakajima
authors: Makoto
authors: M
authors: Takazawa
authors: Koichi
authors: K
authors: Nakagawa
mesh_terms: D000328:Adult; D000368:Aged; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D055959:Intervertebral Disc Degeneration / Q000150:complications / Q000378:metabolism*; D007405:Intervertebral Disc Displacement / Q000150:complications / Q000378:metabolism*; D017116:Low Back Pain / Q000209:etiology / Q000378:metabolism*; D008159:Lumbar Vertebrae; D008297:Male; D008875:Middle Aged; D020932:Nerve Growth Factor / Q000096:biosynthesis*; D010147:Pain Measurement
chemical_list: D020932:Nerve Growth Factor