title: [Effect of intrathecal sufentanil and protein kinase C inhibitor on pain threshold and the expression of NMDA receptor/ CGRP in spinal dorsal horn in rats with neuropathic pain].
abstract: OBJECTIVE
  To investigate the effect of intrathecal sufentanil and protein kinase C inhibitor on pain threshold and the expression of N-methyl-D-aspartate receaptors (NMDAR)/calcitonin generelated peptide (CGRP) in spinal dorsal horn in rats with neuropathic pain.
  
  
  METHODS
  Fifty-four healthy male Sprague-Dawley rats were randomly divided into 6 groups (9 in each group). The rats in the sham group(Group S) + spared nerve injury (SNI), SP+SNI, and P+SNI were intrathecally injected sufentanil (1 μg), sufentanil (1 μg) and chelerythrine chloride (11 μg), chelerythrine chloride (11 μg) followed by 10 μL normal saline once every day for 14 days postoperatively, respectively. Similarly, rats in the control group (Group C), the sham group (Group S), and SNI model group (Group SNI) were intrathecally injected 20 μL normal saline in the uniform interval. Pain behaviours were measured on Day 1 pre-surgery and on Day 1, 2, 7, and 14 after the intrathecal injection. The expressions of NMDAR and CGRP in the spinal dorsal horn of L5 segment were determined by immunohistochemistry on Day 2, 7, and 14 after the intrathecal injection.
  
  
  RESULTS
  Compared with Group C and Group S, mechanical allodynia threshold in group SNI was decreased after the surgery (P<0.01), and expressions of NMDAR and CGRP immunoreactive soma in the spinal dorsal horn was significantly increased (P<0.01). Mechanical stimulation pain threshold was elevated in Group S+SNI, Group P+SNI, and Group SP+SNI compared with Group SNI (P<0.01), while expressions of NMDAR and CGRP immunoreactive soma in Group S+SNI, Group P +SNI, and Group SP+SNI were significantly decreased (P<0.05 or 0.01).
  
  
  CONCLUSIONS
  Intrathecal administration of sulfentanil and protein kinase C inhibitor can provide significant antinociception in rats with neuropathic pain and obviously inhibit the upregulation of NMDAR and CGRP expressions in the spinal dorsal horn of SNI rat models.
authors.affiliation: Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha 410008, China.
authors.forename: Yichun
authors.initials: Y
authors.lastname: Wang
authors.forename: Qulian
authors.initials: Q
authors.lastname: Guo
authors.forename: Mingde
authors.initials: M
authors.lastname: Wang
authors.forename: E
authors.initials: E
authors.lastname: Wang
authors.forename: Wangyuan
authors.initials: W
authors.lastname: Zou
authors.forename: Jianghong
authors.initials: J
authors.lastname: Zhao
mesh_terms: D000818:Animals; D053119:Benzophenanthridines / Q000008:administration & dosage; D015740:Calcitonin Gene-Related Peptide / Q000378:metabolism*; D007278:Injections, Spinal; D008297:Male; D009437:Neuralgia / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D010147:Pain Measurement; D020671:Posterior Horn Cells / Q000378:metabolism; D011493:Protein Kinase C / Q000037:antagonists & inhibitors*; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism*; D017409:Sufentanil / Q000008:administration & dosage*
chemical_list: D053119:Benzophenanthridines; D016194:Receptors, N-Methyl-D-Aspartate; D017409:Sufentanil; C016299:chelerythrine; D011493:Protein Kinase C; D015740:Calcitonin Gene-Related Peptide