title: [Changes of Mu-opioid receptor and neuron-restrictive silencer factor in periaquductal gray in mouse models of remifentanil-induced postoperative hyperalgesia].
abstract: OBJECTIVE
  To determine the changes of Mu-opioid receptor (Mor) and neuron-restrictive silencer factor (NRSF) in periaquductal gray (PAG) in mouse models of remifentanil-induced postoperative hyperalgesia.
  
  
  METHODS
  Thirty-two Kun-Ming mice were randomly divided into 4 groups (8 mice in each group): Group C (mice underwent a sham procedure and saline was infused subcutaneously over a period of 30 min), Group I (mice underwent a surgical incision and the same volume of saline), Group R (mice underwent a sham procedure and remifentanil was infused subcutaneously at the moment of surgical incision over a period of 30 min), and group IR (mice underwent a surgical incision and remifentanil). Paw withdrawal mechanical threshold (PWMT) and paw withdrawal thermal latency (PWTL) tests were performed 24 h before the operation and 2, 6, 24, and 48 h after the operation. The specimens were collected after behavioral testings at 48 h. The expressions of Mor and NRSF in mice's PAG neurons were determined by Western blot.
  
  
  RESULTS
  Mechanical allodynia and thermal hyperalgesia developed in Group I, R and IR (P<0.01). Intraoperative infusion of remifentanil enhanced mechanical allodynia and thermal hyperalgesia in mice with planta incision (P<0.01). In Group R and Group IR, the expression of Mor was significantly lower (P<0.01) and NRSF was significantly higher (P<0.01) when compared with Group C and Group I.
  
  
  CONCLUSIONS
  Intraoperative infusion of remifentanil induces postoperative hyperalgesia in mouse models, accompanied with decreased expressions of Mor and increased of NRSF level in PAG neurons, which may be involved in remifentanil induced hyperalgesia.
authors.affiliation: Drum Tower Clinical Medical College of Nanjing Medical University, Nanjing 210008,China.
authors.forename: Mingjian
authors.initials: M
authors.lastname: Kong
authors.forename: Linyu
authors.initials: L
authors.lastname: Shi
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhou
authors.forename: Jianhua
authors.initials: J
authors.lastname: He
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Gu
authors.forename: Juan
authors.initials: J
authors.lastname: Zhang
authors.forename: Zhengliang
authors.initials: Z
authors.lastname: Ma
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D006930:Hyperalgesia / Q000139:chemically induced*; D051379:Mice; D010149:Postoperative Pain; D010487:Periaqueductal Gray / Q000187:drug effects / Q000378:metabolism*; D010880:Piperidines / Q000008:administration & dosage; D017450:Receptors, Opioid, mu / Q000378:metabolism*; D000077208:Remifentanil; D012097:Repressor Proteins / Q000378:metabolism*; D000099229:RE1-Silencing Transcription Factor
chemical_list: D010880:Piperidines; D017450:Receptors, Opioid, mu; D000077208:Remifentanil; D012097:Repressor Proteins; D000099229:RE1-Silencing Transcription Factor