OBJECTIVE: To probe into the bidirectional regulation of acupuncture in the rat with motility abnormality of the stomach and the nerve mechanism. METHODS: Adopting electrophysiological methods, the extracellular discharge signals of neuronic action in NTS were recorded with glass microelectrodes. The effects of acupuncture at "Zusanli" (ST 36), "Neiguan" (PC 6), "Zhongwan" (CV 12), "Qihai" (CV 6) on discharges of NTS neurons and intra-gastric pressure were observed in the rat at normal physiological state, and increase or reduction of gastric motility. RESULTS: Acupuncture at "Zusanli" (ST 36), "Neiguan" (PC 6) could significantly promote gastric motility of the rat at normal status, increase or reduction of gastric motion, while acupuncture at "Zhongwan" (CV 12), "Qihai" (CV 6) could significantly inhibit gastric motion. And acupuncture at all the above acupoints could activate discharges of NTS neurons. CONCLUSION: The bidirectional regulation effect of an acupoint does not certainly indicate that the same point has bidirectional regulation effect on an internal organs at different pathological states, while this may show synthetic action of different points which is a good regulation towards normal states and homeostasis.