Effect of Tongbiantang on PKA/MPKA Signal Pathway in Colon Tissue of STC Rat Model / 中国实验方剂学杂志

ABSTRACT

Objective: To explore the effect of Tongbiantang on protein kinase A(PKA) and mitogen-activated protein kinase(MAPK) signal pathway in colon tissue of slow transit constipation(STC) rats and its related mechanism. Method: Eighty SD rats were randomly divided into blank group and model group, 20 rats in blank group, 60 rats in model group, half male and half female; blank group was fed with common diet, model group was fed with compound phenylethylpiperidine, after 120 days of modeling, 10 rats in blank group and 20 rats in model group were randomly selected, and 2 rats were determined. Four-hour stool volume, water content and small intestinal charcoal powder propelling rate were observed to observe the number of stool particles retained in colon and evaluate the success of STC rat modeling. After 1 week of drug withdrawal, 40 rats in model group were randomly divided into model group(33 g·kg-1), Tongbiantang group, Tongbiantang+H89 group (PKA signaling pathway blocker,5 mg·kg-1), Tongbiantang+U0126 group (MPKA signaling pathway blocker,0.1 mg·kg-1) each. After 4 weeks of intervention with Tongbiantang, the amount of stool excretion, water content and small intestinal charcoal powder propelling rate were measured in 10 rats, and the number of stool grains in colon was observed. The protein content and mRNA expression in aquaporins 3(AQP3), AQP4, PKA and MAPKs signaling pathways in colon was determined by immunohistochemical staining (IHC), Western blot and Real-time fluorescence quantitative PCR (Real-time PCR). Result: Compared with the blank group, the 24-hour stool volume, fecal water content, small intestinal charcoal propelling rate and the number of fecal particles in colon of rats in the model group were significantly decreased (PPPPPConclusion: Tongbiantang can inhibit the PKA and MPKA signal pathways, thus down-regulate the expression of AQP3 and AQP4, increase intestinal peristalsis and intestinal water, and effectively treat STC.