[Acupuncture inhibiting responses of spinal dorsal dorsal horn neurons induced by noxious dilation rectum and colon].
OBJECTIVE
To study on mechanisms of acupuncture in relieving visceral pain.


METHODS
In SD rats CRD was used as noxious visceral stimuli. Activities of spinal dorsal horn wide dynamic (WDR) neurons of L1-L13 were recorded by extracellular microelectrode technique. Acupuncture was given at ipsi-lateral and contra-lateral Zusanli (ST 36) of the same segmental innervation of rectum and colon.


RESULTS
Visceral noxious afferent could significantly activate spinal dorsal horn convergent neurons, and mechanical stimulation of contra-lateral body surface and hand acupuncture at Zusanli (ST 36) could inhibit this noxious response. When the spinal cord was acutely blocked, the inhibiting CRD effect of needling CRD effect of needling contra-lateral Zusanli (ST 36) completely disappeared.


CONCLUSIONS
Acupuncture and visceral noxious afferent signals converge and interact each other in spinal level, and acupuncture at acupoint can inhibit the spinal dorsal horn neuron respon se activated by visceral noxious afferent and this action needs the participation of the center above the spinal cord.
Rong
Pei-jing
PJ
Institute of Acupuncture & Moxibustion, China Academy of TCM, Beijing 100700, China. rongpj@vip.sina.com
Zhu
Bing
B
Huang
Qi-fu
QF
Gao
Xin-yan
XY
Ben
Hui
H
Li
Yan-hua
YH
D000818:Animals; D003106:Colon / Q000294:innervation; D009619:Nociceptors; D020671:Posterior Horn Cells; D017207:Rats, Sprague-Dawley; D012007:Rectum; D013116:Spinal Cord