[The analgesic extensiveness and specificity of EA at different points on nociceptive response of trigeminal convergent neurons (TCN)].
Our privious work have demonstrated that eletroacupuncture (EA) at acupoints seemed to have no specific effects. The present work is to observe whether the analgesic extensiveness and specificity of EA at points is related to EA intensity and the sites of points. Experiments were carried out on rats anaesthetized with Urathane. The spontaneous discharges and nociceptive responses of convergent neurons on right trigeminal dorsl horn to noxious stimulation at receptive field (cheek) were recorded extracellarly with glass micro-electrode. EA was applied at ipsilateral "Xiaguan" (on face) or "Zusanli" (on shank) point with low (2V) and high (18V) intensity. The nociceptive response of TCN could be inhibited by low intensity EA applied at "Xiaguan" but not "Zusanli", showing the specificity of points. High intensity EA at either "Xiaguan" or "Zusanli" also reduced the responses, showing the analgesic extensiveness of points. We suggest that "the gate of control" mechanism plays an important role in low intensity EA and "DNIC" mechanism does so in high intensity EA. The results suggest that we must pay attention to the manipulation and the intensity of acupuncture in the clinic work.
Xu
W
W
Institute of Acupuncture and Moxibution, China Academy of TCM, Beijing.
Liu
X
X
Zhu
B
B
He
X
X
Zhang
S
S
D015667:Acupuncture Analgesia; D015669:Acupuncture Points; D000818:Animals; D015671:Electroacupuncture; D009474:Neurons / Q000502:physiology; D051381:Rats; D014278:Trigeminal Nuclei / Q000502:physiology*