[Novel exploration of cathartic pharmacology induced by rhubarb]

Rhubarb is well-known for its cathartic effect, and this cathartic effect, which is closely correlated with "whter" of traditional Chinese medicine (TCM), is brought into play in colon. Recent researches about the relation between formation and effects have identified that the anthraquinone glycosides with 1,8-dio-hydroxy and without hydroxyl in the 2, 3, 6, 7 location, such as emodin, rhein, chrysophanol, et al, can bring about fairly obvious effects of "Watery Diarrhea". Aquaporins (AQPs) are expressed abundantly in colonic epithelial cells, and the abnormal expression of AQPs can lead to the less absorption of water in colon and/or the more secretion of intestinal juice, which suggest that AQPs might be one kind of the effector molecules, which some drugs playing pharmacologic actions in colon depend on. This assumption provides a novel field of vision. Is this "Watery Diarrhea" effect induced by rhubarb concerned with the location alteration or the expression change of AQPs. We deduce that the regulative effects of AQPs by rhubarb in colon might provide a new pharmacologic explation about the cathartic effect through the exploration of TCM and Chinese herbal drugs, with TCM theory and the analysis of data about efficiency and pharmacologic researches of rhubarb and the researches of AQPs. This deduction might be used to reveal why rhubarb can bring about multi-efficiency.