OBJECTIVETo observe the regional homogeneity (ReHo) of resting-state brain function in the healthy subjects of gastric distention treated with acupuncture at the back- and front- points of the stomach, Weishu (BL 21) and Zhongwan (CV 12) and the correlation with gastric motility so as to explore the mechanism on the central integration of the front- and back- points of the stomach.

METHODSThe crossover test design was adopted. Twenty-four healthy subjects were assigned to a Weishu group, a Zhongwan group and a combined-point group separately, 8 cases in each one in each of the three times. Totally, 24 subjects were included in each group. Under the water load condition, the subjects received acupuncture at Weishu (BL 21), Zhongwan (CV 12) and the combined Weishu (BL 21) and Zhongwan (CV 12). Before and after each acupuncture, the resting-state brain functional magnetic resonance imaging (fMRI) scan and electrogastrogram (EGG) test were applied. The ReHo value was calculated in the collected fMRI imaging data. The changes in ReHo values were analyzed and compared before and after acupuncture in each group, as well as among the groups. The gastric motility was analyzed before and after acupuncture. Additionally, the correlative analysis was conducted between the gastric motility and ReHo changes before and after acupuncture.

RESULTS(1) After acupuncture, EGG amplitudes in the subjects of each group were lower remarkably as compared with those before acupuncture (all <0.01). The EGG frequencies were not different significantly as compared with those before acupuncture (all >0.05). The EGG amplitudes in the Weishu group and the Zhongwan group were higher than those in the combined-point group (both <0.05). (2) As compared with the conditions before acupuncture, acupuncture at the combined front- and the back- points as well as Weishu (BL 21) and Zhongwan (CV 12) separately all induced the changes in the brain ReHo. Acupuncture at the combined front- and the back- points significantly increased Reho values in the right inferior temporal gyrus, the left thalamus, the precuneus and the posterior cingulate gyrus (all <0.05) and remarkably reduced the ReHo values in the the middle temporal gyrus of the right temporal pole, sulcus calcarinus and precuneus (all <0.05). Compared with the single point groups, acupuncture at the combined front- and the back- points induced the increase of ReHo value in the posterior cingulate gyrus and the decrease of ReHo in the temporal pole (all <0.05). (3) The correlative analysis showed that the changes in the ReHo values in the posterior cingulate gyrus, the thalamus and the precuneus were positively correlated to the changes of the gastric motility amplitudes. The changes in the ReHo values in the temporal pole was negatively correlated to the changes of the gastric motility amplitudes.

CONCLUSIONAcupuncture at the combined back- and front- points of the stomach, as well as acupuncture at single Weishu (BL 21) and Zhongwan (CV 12) induce the ReHo changes in the different brain regions. Acupuncture at the combined back- and front- points of the stomach may induce the ReHo changes in some new brain regions as compared with the acupuncture at the single point. The thalamus, the posterior cingulate gyrus and the precuneus may be the the important integrated brain regions for acupuncture at the back- and the front- points in regulating the gastric motility. The effects of acupuncture at the back- and the front- points for the regulation of the gastric motility are closely related to the thalamus, the limbic system and the default network of the brain regions.