title: [Effects of electroacupuncture at "Futu" (LI 18), etc. on expression of spinal 5-HT 1 AR mRNA, 5-HT 2 AR mRNA and protein in rats with neck incision pain].
abstract: OBJECTIVE
  To observe the effect of electroacupuncture (EA) at bilateral "Futu" (LI 18), etc. on the expression of 5-HT 1 A receptor (R) mRNA, 5-HT2 AR mRNA and protein in the spinal cord of rats with neck incision pain, so as to explore its underlying mechanism in relieving incision pain.
  
  
  METHODS
  A total of 48 Wistar rats were randomly divided into control, model (incision pain), Futu (LI 18), Hegu (LI 4)-Neiguan (PC 6, LI 4-PC 6), Zusanli (ST 36)-Yanglingquan (GB 34) cervical cord (ST 36-GB 34 C) and lumbar cord (ST 36-GB 34 L) groups. A 1.5 cm longitudinal incision was made in the middle of the neck under Isoflurane inhalation anesthesia. Pain threshold (PT) was measured using radiant heat. EA (1-2 mA, 2 Hz/15 Hz) was applied to bilateral LI 18, LI 4-PC 6, ST 36-GB 34 for 30 min. The expression of 5-HT 1 AR mRNA, 5-HT 2 AR mRNA and protein in the cervical spinal cord (C1-C4) tissue, and 5-HT 1 AR mRNA and 5-HT 2 AR mRNA in the lumbar cord (L1- L3) were detected with Real-time PCR and Western blot analysis, respectively.
  
  
  RESULTS
  After the operation, the thermal PT was shortened obviously In comparison with pre-operation (P < 0.05). Compared with post-operation, the PT values were increased markedly in the LI 18 group and LI 4-PC 6 group (P < 0.05), rather than in the ST 36-GB 34 group (P > 0.05). The expression levels of 5-HT 1 AR mRNA, 5-HT 2 AR mRNA and 5-HT 2 AR protein in the cervical cord of the model group were increased significantly compared with those of the control group (P < 0.05). In comparison with the model group, the expression level of 5-HT 1 AR mRNA was down-regulated considerably in the LI 18 and LI 4-PC 6 groups (P < 0.05), and those of spinal 5-HT 2 AR mRNA and protein were up-regulated significantly in the LI 18 and LI 4-PC 6 groups (P < 0.05). No significant changes were found in the expression of 5-HT 1 AR mRNA and 5-HT 2 AR mRNA in the ST 36-GB 34 C group in comparison with the model group (P > 0.05). The expression levels of 5-HT 1 AR mRNA and 5-HT 2 AR mRNA in the ST 36-GB 34 L group were significantly lower than those of the ST 36-GB 34 C group (P < 0.05).
  
  
  CONCLUSIONS
  EA of LI 18 and LI 4-PC 6 can significantly suppress pain reaction of neck incision in the rat, which is closely associated with its effects in down-regulating the expression of 5-HT 1 AR mRNA and in up-regulating 5-HT 2 AR mRNA and 5-HT 2 AR protein in the cervical spinal cord.
authors.affiliation: Institute of Acu-moxibustion, China Academy of Chinese Medical Sciences, Beijing 100700, China.
authors.forename: Li-Na
authors.initials: LN
authors.lastname: Qiao
authors.forename: Yong-Sheng
authors.initials: YS
authors.lastname: Yang
authors.forename: Jun-Ying
authors.initials: JY
authors.lastname: Wang
authors.forename: Yong-Hui
authors.initials: YH
authors.lastname: Gao
authors.forename: Yan-Jing
authors.initials: YJ
authors.lastname: Han
authors.forename: Shu-Ping
authors.initials: SP
authors.lastname: Chen
authors.forename: Chang-Fu
authors.initials: CF
authors.lastname: Ji
authors.forename: Jun-Ling
authors.initials: JL
authors.lastname: Liu
mesh_terms: D015667:Acupuncture Analgesia; D015669:Acupuncture Points; D000818:Animals; D004195:Disease Models, Animal; D015671:Electroacupuncture; D006801:Humans; D008297:Male; D009333:Neck / Q000601:surgery*; D010149:Postoperative Pain / Q000235:genetics* / Q000378:metabolism / Q000628:therapy*; D051381:Rats; D017208:Rats, Wistar; D044282:Receptor, Serotonin, 5-HT1A / Q000235:genetics* / Q000378:metabolism; D044402:Receptor, Serotonin, 5-HT2A / Q000235:genetics* / Q000378:metabolism; D013116:Spinal Cord / Q000378:metabolism*
chemical_list: D044402:Receptor, Serotonin, 5-HT2A; D044282:Receptor, Serotonin, 5-HT1A