Zhen Ci Yan Jiu. 1992 ; 17(2): 90-5.

[Effect of electro-acupuncture on the nociceptive responses of SI cortical neurons in the rat]

Yaun B, Liu X.

Research Laboratory of Neurophysiology, Xi'an Medical University, Shaaxi.

1. The effect of electro-acupuncture (EA) on the responses of single SI cortical nociceptive neurons to peripheral natural stimuli were observed in unanesthetized and paralyzed rats. 2. After EA, the responses to noxious mechanical and/or thermal stimulation reduced markedly in 14 (70%) out of 20 neurons tested, and slightly increased or unchanged in the remaining 6 neurons, as compared to the responses before EA. 3. In contrast to the variation of nociceptive responses, the responses to innocuous mechanical stimulation increased in 9 neurons and unchanged in other 9 neurons, while deceased in only 2 neurons. 4. A small portion of the neurons were activated by EA stimulation, while their responses to noxious stimulation were inhibited. 5. It is considered that the selective inhibition of the nociceptive responses of SI cortical neurons might be a part of the mechanisms of acupuncture analgesia.