title: Changes in expression of cyclooxygenase-2 in the spinal dorsal horn after intrathecal p38MAPK inhibitor SB203580 on neuropathic pain in rats.
abstract: OBJECTIVE
  To investigate the changes of cyclooxygenase-2 (COX-2) expression in the spinal cord dorsal horn after intrathecal a specific p38MAPK inhibitor-SB203580 on neuropathic pain in rats induced by chronic constrictive injury (CCI) to the sciatic nerve.
  
  
  METHODS
  Twenty-four male SD rats after intrathecal catheter placement were randomly divided into 4 groups: a sham group with sham surgery, the neuropathic pain model of a NS group, a DMSO group and an SB group were established by CCI to sciatic nerve. NS or DMSO or SB203580 was injected IT NS or 2% DMSO or SB203580 twice a day for 5 consecutive days starting at 6th day when the model of CCI was established. Mechanical stimuli were measured before the surgery and on 1st, 3rd, 5th, 7th, 9th, and 11th day after the surgery. Then all rats were sacrificed and the lumbar segment of spinal cord was removed to determine the COX-2 expression in the dorsal horn by immunocytochemistry.
  
  
  RESULTS
  Day 1 to 11 after the surgery, the threshold to mechanical on the surgery side was significantly lower in the NS group and the DMSO group than in the sham group. Day 7 to 11 after the surgery, the threshold to mechanical on the surgery side was significantly lower in the SB group than in the NS group and the DMSO group. The expression of spinal COX-2 was higher in the NS group and the DMSO group than in the sham group, but lower in the SB group than in NS group and the DMSO group.
authors.affiliation: Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha 410008, Department of Anesthesiology, Lixian People's Hospital of Hunan Province, Lixian 415500, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Wang
authors.affiliation: Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha 410008, China.
authors.forename: Changsheng
authors.initials: C
authors.lastname: Huang
authors.affiliation: Department of Anesthesiology, Hunan Provincial Tumor Hospital, Changsha 410013, China.
authors.forename: Yichun
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha 410008, China. qulianguo@hotmail.com.
authors.forename: Qulian
authors.initials: Q
authors.lastname: Guo
authors.affiliation: Department of Pathology, Xiangya School of Medicine, Central South University, Changsha 410078, China.
authors.forename: Haiying
authors.initials: H
authors.lastname: Jiang
authors.affiliation: Department of Pathology, Xiangya School of Medicine, Central South University, Changsha 410078, China.
authors.forename: Jifang
authors.initials: J
authors.lastname: Wen
keywords: Intrathecal injection; cyclooxygenase-2 (COX-2); neuropathic pain; p38 mitogen activated protein kinase