Effect of electroacupuncture at "Neiguan" (PC 6) and "Zusanli" (ST 36) on gastrointestinal hormone in the antral tissue of rats with functional dyspepsia / 中国针灸

ABSTRACT

OBJECTIVES@#To observe the effects of electroacupuncture (EA) at "Neiguan" (PC 6) and "Zusanli"(ST 36) on the gastric emptying rate, the level of serotonin (5-HT) and the protein expression of motilin (MTL), ghrelin, substance P (SP) and vasoactive intestinal peptide (VIP) in the antral tissue of the rats with functional dyspepsia (FD) and explore the effect mechanism of EA in treatment of FD.@*METHODS@#A total of 21 SPF male SD rat pups were randomly divided into a normal group, a model group and an EA group, with 7 rats in each group. In the model group and the EA group, FD model was prepared by the gavage with 0.1% sucrose iodoacetamide solution combined with the modified small platform method. After the successful modeling, EA was applied to "Neiguan" (PC 6) and "Zusanli"(ST 36) in the rats of the EA group, with disperse-dense wave, 20 Hz/100 Hz in frequency, stimulated for 30 min, once daily, for 7 days consecutively. Before and after intervention, the general condition of the rats was observed in each group. After the completion of intervention, the gastric emptying rate was measured, the morphological changes of gastric antral tissue were observed using HE staining, the level of 5-HT was detected with ELISA method, and the protein expression of MTL, ghrelin, SP, and VIP was determined with Western blot method in the antral tissue of rats.@*RESULTS@#In the normal group, the rats were in a good mental state, with lustrous fur, flexible movement and the increase of food intake and body mass. In the model group, the rats were poor in mental state, lack of lustre in fur, preference for the body curled up, reduced activity and response; and a part of rats had loose stool, obviously enlarged gastric body and gastric food retention. In the EA group, the general condition of rats, e.g. the mental state, food intake and activity, were improved, the gastric body got smaller obviously and the gastric food retention was reduced when compared with the model group. The antral structure was intact, the glands were rich and no injury of the gastric mucosa was found, e.g. inflammatory reaction and edema in the rats of each group. Compared with the normal group, the gastric emptying rate was decreased (P<0.01), 5-HT level was increased (P<0.01), the protein expression of MTL and ghrelin was reduced (P<0.01) and that of VIP was elevated (P<0.01) in the rats of the model group. The gastric emptying rate was increased (P<0.01), 5-HT level was decreased (P<0.01), and the protein expression of MTL and ghrelin was elevated (P<0.05, P<0.01) in the rats of the EA group when compared with those in the model group.@*CONCLUSIONS@#Electroacupuncture at "Neiguan" (PC 6) and "Zusanli"(ST 36) may effectively relieve gastric dysfunction, strengthen gastric motility and promote gastric emptying so as to alleviate the symptoms of dyspepsia in FD rats, and its mechanism may be related to the regulation of gastrointestinal hormones in the antral tissue.