Objective: To observe the effect of acupuncture of "Zusanli" (ST 36) and "Taichong" (LR 3) on gastrointestinal hormone levels in diarrhea type irritable bowel syndrome (IBS-D) rats so as to provide experimental evidence for acupuncture treatment of IBS-D.
Methods: Forty-eight Wistar rats were randomly divided into control, model, acupuncture and medication groups, with 12 rats in each group. IBS-D model was established by chronic mild restraining stress combined with isolated raising and intragastric administration of Folium Sennae (10 mL/kg). For rats of the acupuncture group, bilateral "Zusanli" (ST 36) and "Taichong" (LR 3) were punctured and stimulated for 30 min, once daily for 14 days. The rats of the medication group were treated by gavage of Pinaverin bromide, once daily for 14 days, and those of the control and model groups were given with equal volume of saline. Somatostatin (SS), substance P (SP) and vasoactive intestinal peptide (VIP) in the rats' plasma and ileum tissues were detected by sandwich enzyme-linked immunosorbent assay (ELISA).
Results: Compared with the control group, the body weight and food intake quantity were reduced significantly, while the diarrhea index was increased significantly in the model group (P < 0.05, P < 0.01). In comparison with the model group, the body weight and food intake volume in both acupuncture and medication groups were increased remarkably after the treatment (P < 0.05, P < 0.01) whereas the diarrhea index in the latter two groups was reduced obviously (P < 0.01). Compared with the control group, plasma VIP level was increased significantly in the model group (P < 0.01), while those in both acupuncture and medication groups were decreased remarkably compared with the model group (P < 0.05). No significant changes of plasma SP and SS levels were found after modeling and after both acupuncture and medication treatments. In comparison with the control group, ileum SP, VIP and SS levels in the model group were up-regulated significantly (P < 0.01), while those in both acupuncture and medication groups were down-regulated considerably compared with the model group (P < 0.01). No significant differences were found between acupuncture and medication groups in the levels of ileum SP, VIP and SS (P > 0.05).
Conclusion: Acupuncture of ST 36 and LR 3 can effectively down-regulate ileum SP, VIP and SS levels in IBS-D rats, which may contribute to its effect in relieving IBS-D.