Neural mechanism of acupuncture-modulated gastric motility

Figure 1 Gastric motility response to electro-acupuncture stimulation with different intensities. Gastric motility was recorded for 90 s, of which the first 20 s was the duration of spontaneous background of gastric activity, 21-50 s was the period of acupuncture stimulation at acupoints, poststimuli activity was recorded for 51-90 s. Dash line represents located abdominal acupoints.

Figure 2 Quantitative analysis of gastric motility in strength-dependent response to electro-acu puncture-stimulation applied to the acupoints on different parts of body. “< Aδ“: the intensity of the stimulation less than the threshold for activation of Aδ-fiber; “> Aδ < C”: the intensity of the stimulation over the threshold for activation of Aδ-fiber, but less than the threshold for activation of C-fiber; “> C”: the intensity of the stimulation over the threshold for activation of C-fiber.

Figure 3 Gastric motility and autonomic nerve responses to acupuncture stimulation at different acupoints. In each acupoint stimulus, gastric motility (GM), activities of gastric vagal (vagus) and postganglionic sympathetic nerve branches to the stomach (symp), were simultaneously recorded.

Figure 4 Effect of acupuncture stimulation on gastric motility in animals with intact autonomic nervous system, after sympathectomy of bilateral splanchnic nerves just beneath the diaphragm but intact vagi and bilateral subdiaphragmatic vagotomy but intact sympathetic nerve.

Figure 5 Analysis of the changes in gastric motility induced by acupuncture stimulation in rats after bilateral sympathectomy (A) of splanchnic nerves and vagotomy (B), respectively. ^aP < 0.05, ^bP < 0.01 and ^dP < 0.001 vs animals with intact autonomic nervous system.

Figure 6 Effects of acupuncture stimulation involving the supraspinal circuit on gastric motility in normal (A) and spinalized (B) rats.

Figure 7 Effects of acupuncture stimulation at different acupoints on the regulation of gastric motility in normal and spinalized rats. Triangle-lines represent the pre-spinalized effects and square-lines indicate the post-spinalized effects. ^aP < 0.05, ^bP < 0.01 and ^dP < 0.001 vs the control gastric motility of pre-spinalization.