title: [Targeted damage of the cerebrospinal fluid-contacting nucleus contributes to the pain behavior and the expression of 5-HT and c-Fos in spinal dorsal horn of rats].
abstract: OBJECTIVE
  The changes of pain threshold and expression of 5-hydroxytryptamine(5-HT) and c-Fos in spinal dorsal horn of rats were observed after targetedly damaged the cerebraspinal fluid-contacting nucleus (CSF-contacting nucleus) to provide experimental evidence for the mechanism of regulating pain CSF-contacting nucleus involved in.
  
  
  METHODS
  Male adult SD rats were divided into control, sham, choleratoxin subunit B conjugated with horse-radish peroxidase (CB-HRP)and damage groups randomly. The pain threshold using mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) were recorded and analyzed. Immunofluorescence method was used to observe the expression of 5-HT and c-Fos in spinal dorsal horn.
  
  
  RESULTS
  Compared with the control, sham and CB-HRP groups, the MWT and TWL of the damage group were significantly increased (P < 0.05). The results of immunofluorescence showed that 5-HT was detected in neurons of CSF-contacting nucleus. In the damage group, the number of neurons of CSF-contacting nucleus reduced gradually, and no survived neurons were observed at the 10th day. Meanwhile, both the expression of 5-HT and c-Fos in spinal dorsal horn increased gradually, and negatively correlated with the change of pain threshold.
  
  
  CONCLUSIONS
  The method of targeted damaging CSF-contacting nucleus by cholera toxin subnit B conjugated with saporin(CB-SAP) is scientific and reliable, and it results in the changes of pain threshold and expression of 5-HT and c-Fos in spinal dorsal horn of rats. This study suggests that CSF-contacting nucleus participate in the regulation of pain, moreover, 5-HT and c-Fos play important roles in this regulation.
authors.forename: Jing
authors.initials: J
authors.lastname: Cao
authors.forename: Tong
authors.initials: T
authors.lastname: Wu
authors.forename: Li-Cai
authors.initials: LC
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002555:Cerebrospinal Fluid; D008297:Male; D010146:Pain / Q000378:metabolism / Q000601:surgery*; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012701:Serotonin / Q000378:metabolism*; D066148:Spinal Cord Dorsal Horn / Q000378:metabolism*
chemical_list: D016760:Proto-Oncogene Proteins c-fos; D012701:Serotonin