title: Remote dose-dependent effects of dry needling at distant myofascial trigger spots of rabbit skeletal muscles on reduction of substance P levels of proximal muscle and spinal cords.
abstract: BACKGROUND
  Dry needling at distant myofascial trigger points is an effective pain management in patients with myofascial pain. However, the biochemical effects of remote dry needling are not well understood. This study evaluates the remote effects of dry needling with different dosages on the expressions of substance P (SP) in the proximal muscle, spinal dorsal horns of rabbits.
  
  
  METHODS
  Male New Zealand rabbits (2.5-3.0 kg) received dry needling at myofascial trigger spots of a gastrocnemius (distant muscle) in one (1D) or five sessions (5D). Bilateral biceps femoris (proximal muscles) and superficial laminaes of L5-S2, T2-T5, and C2-C5 were sampled immediately and 5 days after dry needling to determine the levels of SP using immunohistochemistry and western blot.
  
  
  RESULTS
  Immediately after dry needling for 1D and 5D, the expressions of SP were significantly decreased in ipsilateral biceps femoris and bilateral spinal superficial laminaes (P < .05). Five days after dry needling, these reduced immunoactivities of SP were found only in animals receiving 5D dry needling (P < .05).
  
  
  CONCLUSIONS
  This remote effect of dry needling involves the reduction of SP levels in proximal muscle and spinal superficial laminaes, which may be closely associated with the control of myofascial pain.
authors.affiliation: Department of Physical Therapy, Graduate Institute of Rehabilitation Science, China Medical University, Taichung 40402, Taiwan.
authors.forename: Yueh-Ling
authors.initials: YL
authors.lastname: Hsieh
authors.affiliation: Department of Physical Medicine and Rehabilitation, Cheng Ching General Hospital, Taichung 40407, Taiwan.
authors.forename: Chen-Chia
authors.identifier: 0000-0003-0601-7965
authors.initials: CC
authors.lastname: Yang
authors.affiliation: Department of Physical Therapy, Graduate Institute of Rehabilitation Science, China Medical University, Taichung 40402, Taiwan.
authors.forename: Szu-Yu
authors.initials: SY
authors.lastname: Liu
authors.affiliation: School of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung 40402, Taiwan ; Department of Physical Medicine and Rehabilitation, China Medical University Hospital, Taichung 40402, Taiwan ; Research Center for Chinese Medicine and Acupuncture, China Medical University, Taichung 40402, Taiwan.
authors.forename: Li-Wei
authors.identifier: 0000-0002-3540-6225
authors.initials: LW
authors.lastname: Chou
authors.affiliation: Department of Physical Therapy, Hungkuang University, Taichung 43302, Taiwan.
authors.forename: Chang-Zern
authors.initials: CZ
authors.lastname: Hong
mesh_terms: D015669:Acupuncture Points; D015670:Acupuncture Therapy; D000818:Animals; D008297:Male; D009045:Motor Endplate / Q000502:physiology; D018482:Muscle, Skeletal / Q000378:metabolism*; D011817:Rabbits; D013116:Spinal Cord / Q000378:metabolism*; D066148:Spinal Cord Dorsal Horn / Q000378:metabolism; D013373:Substance P / Q000378:metabolism*
chemical_list: D013373:Substance P