OBJECTIVE: To observe and compare the effect of electroacupuncture (EA) of "Tianshu" (ST25) and "Dachangshu" (BL25) on intestinal sensitivity and the expression of M3 muscarinic acetylcholine receptor (M3R) and 5-hydroxytryptamine 3A receptor (5-HT3AR) in the colon tissue in irritable bowel syndrome (IBS) rats, so as to explore its mechanism underlying improvement of IBS.