title: Antipruritic effect of cold stimulation at the Quchi acupoint (LI11) in mice.
abstract: BACKGROUND
  Acupuncture and moxibustion are used to treat pruritus and atopic dermatitis. However, whether cold stimulation (defined as that the temperature conducted under skin temperature) of acupoints affects itching in experimental murine models remains unclear.
  
  
  METHODS
  The present study was designed to determine the therapeutic effects of different thermal stimulations at the Quchi acupoint (LI11) in a murine model in which scratching behaviour was elicited by subcutaneous injection with a pruritogenic agent (compound 48/80). Male ICR mice were divided into several groups as follows: control (saline), those receiving compound 48/80 and compound 48/80 with various thermal stimulations (5°C-45°C) at LI11 (n = 6 per group). The scratch response of each animal to these stimulations was recorded for 30 min. The antipruritic effect of the acupoint was further evaluated in LI11 and sham (non-acupoint) groups (n = 6 per group).
  
  
  RESULTS
  Treatment with lower temperature (20°C) at the LI11 acupoint significantly attenuated compound 48/80-induced scratching; however, this antipruritic effect was not observed with stimulation at the sham point. The expression of c-fos in the neuron of the cervical spine induced by compound 48/80 was suppressed by cold stimulation at LI11. The antipruritic effect of cold stimulation was blocked by ruthium red (RR), a non-selective transient receptor potential (TRP) channel blocker, suggesting that TRP channels may play an important role in the antipruritic effect of cold stimulation at LI11 in mice.
  
  
  CONCLUSIONS
  This study demonstrated that cold stimulation at LI11 attenuated compound 48/80-induced scratching behaviour in mice, possibly by a TRP-related pathway.
authors.forename: Kao-Sung
authors.initials: KS
authors.lastname: Tsai
authors.forename: Yung-Hsiang
authors.initials: YH
authors.lastname: Chen
authors.forename: Huey-Yi
authors.initials: HY
authors.lastname: Chen
authors.forename: Ein-Yiao
authors.initials: EY
authors.lastname: Shen
authors.forename: Yu-Chen
authors.initials: YC
authors.lastname: Lee
authors.forename: Jui-Lung
authors.initials: JL
authors.lastname: Shen
authors.forename: San-Yuan
authors.initials: SY
authors.lastname: Wu
authors.forename: Jaung-Geng
authors.initials: JG
authors.lastname: Lin
authors.affiliation: School of Chinese Medicine, Graduate Institute of Integrated Medicine, Graduate Institute of Acupuncture Science, College of Chinese Medicine, Research Center for Chinese Medicine & Acupuncture, China Medical University, Taichung, Taiwan. yihungchen@mail.cmu.edu.tw.
authors.forename: Yi-Hung
authors.initials: YH
authors.lastname: Chen
authors.forename: Wen-Chi
authors.initials: WC
authors.lastname: Chen
mesh_terms: D015669:Acupuncture Points; D015670:Acupuncture Therapy / Q000379:methods*; D000818:Animals; D000982:Antipruritics; D003080:Cold Temperature; D017679:Cryotherapy / Q000379:methods*; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D011537:Pruritus / Q000139:chemically induced / Q000378:metabolism / Q000628:therapy*; D003189:p-Methoxy-N-methylphenethylamine
chemical_list: D000982:Antipruritics; D016760:Proto-Oncogene Proteins c-fos; D003189:p-Methoxy-N-methylphenethylamine