title: Neural mechanism of acupuncture-modulated gastric motility.
abstract: OBJECTIVE
  To investigate the acupuncture-modulated gastric motility and its underlying neural mechanism.
  
  
  METHODS
  Intragastric pressure and/or waves of gastric contraction in rats were recorded by intrapyloric balloon and changes of gastric motility induced by acupuncture stimulation were compared with the background activity before any stimulation. Gastro-vagal or splanchnic-sympathetic nerves were recorded or cut respectively for investigating the involvement of autonomic nerve pathways. Spinalization experiment was also performed.
  
  
  RESULTS
  Acupuncture-stimulation by exciting A delta and/or C afferent fibers, could only modulate gastric motility. Acupuncture-stimulation on fore- and hind-limbs evoked a moderate gastric motility followed by increased vagus discharges with unchanged sympathetic activity, while the same stimulus to the acupoints in abdomen resulted in reversed effects on gastric motility and autonomic nervous activities. The inhibitory gastric response was completely abolished by splanchnic denervation, but the facilitative gastric response to stimulation of acupoints in limbs was not influenced, which was opposite to the effect when vagotomy was performed. The similar depressive effects were produced by the stimulation at the acupoints homo-segmental to the gastric innervation in the animals with or without spinalization. However, the facilitation induced by the stimulation at the acupoints hetero-segmental to the gastric innervation was not observed in the spinalized animals.
  
  
  CONCLUSIONS
  Facilitative effects of stimulating hetero-segmental acupoints are involved in the intact preparation of vagal nerves and spinal cord, while the inhibitory response induced by stimulating homo-segmental acupoints is involved in the intact preparation of sympathetic nerves. Only the acupuncture-stimulation with intensity over the threshold of A delta and/or C afferent fibers can markedly modulate gastrointestinal motility.
authors.affiliation: Institute of Acupuncture-Moxibustion, China Academy of Chinese Medical Sciences, 16 Nanxiaojie of Dongzhimennei, Beijing 100700, China.
authors.forename: Yu-Qing
authors.initials: YQ
authors.lastname: Li
authors.forename: Bing
authors.initials: B
authors.lastname: Zhu
authors.forename: Pei-Jing
authors.initials: PJ
authors.lastname: Rong
authors.forename: Hui
authors.initials: H
authors.lastname: Ben
authors.forename: Yan-Hua
authors.initials: YH
authors.lastname: Li
mesh_terms: D000818:Animals; D015671:Electroacupuncture; D005746:Gastric Emptying / Q000502:physiology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000166:cytology / Q000502:physiology; D013270:Stomach / Q000294:innervation / Q000502:physiology*; D017779:Sympathetic Fibers, Postganglionic / Q000166:cytology / Q000502:physiology; D014630:Vagus Nerve / Q000166:cytology / Q000502:physiology*