Objective: To explore the effect of Xiaofu Tongjie recipe on VIP-cAMP-PKA-AQP3 signaling pathway in colon tissues of rats with functional constipation in rats. Method: Totally 150 SD male rats were randomly divided into normal group

model group

Xiaofu Tongjie recipe high dose

middle dose and low dose groups (380

190

95 g·kg-1)

n=30 in each group. Compound diphenoxylate was applied by ig to induce functional constipation SD rat models

and then different doses of Xiaofu Tongjie recipe were given by ig administration for 4 weeks. The excretion time of first black defecating feces and moisture content in the feces were detected. The Real-time PCR and Western bolt were used respectively to detect the mRNA and protein expression levels of vasoactive intestinal peptide (VIP)

cyclic adenosine monophosphate (cAMP)

protein kinase A (PKA) and aquaporin 3 (AQP3) at different time points after treatment of 1

2

3 weeks. Result: As compared with the normal group

the excretion time of first black defecating feces was significantly prolonged in model group; moisture content in the feces was significantly reduced (P<0.01); the mRNA and protein expression levels of VIP

cAMP

PKA and AQP3 in colon tissues were significantly reduced (P<0.05

P<0.01). As compared with the model group

the excretion time of first black defecating feces was significantly shortened in various Xiaofu Tongjie recipe groups

and the moisture content in the feces was significantly increased (P<0.05

P<0.01); the mRNA and protein expression levels of VIP

cAMP

PKA and AQP3 in colon tissues were increased

and the increase was more obvious in high and middle dose groups; the changes of the indexes at week 2 and week 3 were more obvious than those of week 1 (P<0.05

P<0.01). Conclusion: Xiaofu Tongjie recipe can regulate the intestinal peristalsis and intestinal fluid metabolism and cure the functional constipation in a time and dose-dependent manner

which may be achieved by intervention on VIP-cAMP-PKA-AQP3 signaling pathway.