title: Plasma neuropeptides in patients undergoing lumbar discectomy.
abstract: METHODS
  A prospective analysis of patients with lumbar disc herniation (LDH).
  
  
  OBJECTIVE
  To determine the role of neuropeptides as a biochemical signature of pain states in patients with LDH.
  
  
  BACKGROUND
  Increases in the plasma level of neuropeptides have been reported in patients suffering from a variety of painful conditions. However, there is no such report on patients with LDH.
  
  
  METHODS
  From a total of 27 patients with a single-level LDH, blood samples were collected before and 3 weeks after lumbar discectomy. Plasma levels of alpha calcitonin gene-related peptide (CGRP), galanin, neuropeptide Y, and substance P were determined by using enzyme-linked immunosorbent assay. The association or correlation between preoperative concentration of plasma neuropeptides and gender, patients' age, and VAS were analyzed statistically. Also, the concentration of plasma neuropeptides was compared before and after lumbar discectomy.
  
  
  RESULTS
  Preoperative plasma levels of CGRP were correlated significantly with the extent of sciatica as determined by VAS. In addition, plasma levels of CGRP and galanin significantly decreased after lumbar discectomy in line with the disappearance of pain symptoms.
  
  
  CONCLUSIONS
  These findings indicate the role of plasma CGRP and possibly galanin as a systemic neurochemical signature of pain states in patients with LDH.
authors.affiliation: Department of Orthopaedic Surgery, Sapporo Medical University School of Medicine, Sapporo, Japan.
authors.forename: Hirohito
authors.initials: H
authors.lastname: Takeuchi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kawaguchi
authors.forename: Osamu
authors.initials: O
authors.lastname: Ohwada
authors.forename: Hiroji
authors.initials: H
authors.lastname: Kobayashi
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Hayakawa
authors.forename: Tsuneo
authors.initials: T
authors.lastname: Takebayashi
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Torigoe
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Sato
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Yamashita
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015740:Calcitonin Gene-Related Peptide / Q000097:blood; D017586:Diskectomy; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D019004:Galanin / Q000097:blood; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000097:blood* / Q000150:complications / Q000601:surgery*; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009478:Neuropeptide Y / Q000097:blood; D009479:Neuropeptides / Q000097:blood*; D010147:Pain Measurement; D011184:Postoperative Period; D011300:Preoperative Care; D011446:Prospective Studies; D012585:Sciatica / Q000209:etiology / Q000503:physiopathology; D013373:Substance P / Q000097:blood
chemical_list: D009478:Neuropeptide Y; D009479:Neuropeptides; D013373:Substance P; D019004:Galanin; D015740:Calcitonin Gene-Related Peptide