title: Soluble gp130 regulatess interleukin-6 in cerebrospinal fluid after subarachnoid haemorrhage.
abstract: BACKGROUND
  Interleukin-6 (IL-6) is a proinflammatory cytokine reported to play an important role in induction of cerebral vasospasm after subarachnoid haemorrhage (SAH). Soluble gp130 (sgp130) and soluble IL-6 receptor (sIL-6R) are known to act as signal transducing receptors of IL-6, the former as an antagonist and the latter as an agonist. However, there have been no reports concerning regulation of the IL-6 signalling pathway in cerebrospinal fluid (CSF) after SAH.
  
  
  METHODS
  Concentrations of IL-6, sgp130 and sIL-6R were measured serially until day 14 in CSF from nine patients with SAH. CSF samples obtained from patients suffering from unruptured aneurysm were used as controls. Colocalisation of IL-6 and sgp130 in CSF on day 1 was further examined by immunoprecipitaiton.
  
  
  RESULTS
  Concentrations of IL-6 in CSF increased immediately after the onset of SAH and remained chronically elevated over control values. Both sgp130 and sIL-6R also exhibited increased on day 1, followed by a decrease limited to the gp130 case after day 5. Sgp130 coimmunoprecipitated with IL-6 in CSF on day 1 after SAH.
  
  
  CONCLUSIONS
  Our findings suggest that sgp130 regulates IL-6 signalling as an antagonist in CSF immediately after SAH. As the concentration of sgp130 decreases after day 5, IL-6 signals might then be more easily transmitted, presumably resulting in cerebral vasospasm.
authors.affiliation: Department of Neurological Surgery, Aichi Medical University, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Nakura
authors.forename: Koji
authors.initials: K
authors.lastname: Osuka
authors.forename: Takashi
authors.initials: T
authors.lastname: Inukai
authors.forename: Teruhide
authors.initials: T
authors.lastname: Takagi
authors.forename: Masakazu
authors.initials: M
authors.lastname: Takayasu
mesh_terms: D000328:Adult; D000368:Aged; D050822:Cytokine Receptor gp130 / Q000502:physiology*; D018450:Disease Progression; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D047468:Immunoprecipitation; D015850:Interleukin-6 / Q000134:cerebrospinal fluid*; D008297:Male; D008875:Middle Aged; D015398:Signal Transduction; D013345:Subarachnoid Hemorrhage / Q000134:cerebrospinal fluid*; D013997:Time Factors
chemical_list: D015850:Interleukin-6; D050822:Cytokine Receptor gp130