Objective To observe the effect of electroacupuncture(EA)intervention on constipation-predominant irritable bowel syndrome(C-IBS)and colonic calcitonin gene-related peptide(CGRP)and substance P(SP)expression levels in IBS rats

so as to reveal its mechanism underlying improvement of IBS.Methods A total of 32 male Wistar rats were equally randomized into normal control

model

EA-Shangjuxu(ST 37)and EA-Dachangshu(BL 25)groups.The C-IBS model was established according to Peng's methods(2004).EA(2Hz/100 Hz

0.1-0.2mA)was applied to bilateral ST 37 and BL 25for30 min

once daily for 7days.The stool properties(hardness or softness

water content

etc.)were typed(1-7points)and the fecal water content was calculated by wet weight minus dry weight.The relative expression levels of CGRP and SP proteins in the colon tissues were detected by Western blot.Results Compared to the control group

the stool property score and stool water content were significantly lower in the model group(P<0.01).After EA intervention

both stool property scores and stool water contents were obviously higher in the EA-ST 37 and EA-BL 25 groups than in the model group(P<0.05

P<0.01).The expression levels of colonic CGRP and SP proteins were significantly higher in the model group than in the control group

and obviously down-regulated in the two EA intervention groups(P<0.01).No significant differences were found between the EA-ST 37 and EABL 25 groups in the stool property score and stool water content

and colonic CGRP and SP protein expression levels(P>0.05).Conclusion EA intervention can ameliorate the fecal property in C-IBS rats

which may be associated with its function in inhibiting the expression of colonic CGRP and SP proteins.