%0 Journal Article %T Antidiarrheal activity of methanol extract of Sophora tonkinensis in mice and spasmolytic effect on smooth muscle contraction of isolated jejunum in rabbits %A Jianwu Zhang %A Jing Li %A Qian Zheng %A Rudan Zheng %A Shangjie Zhong %A Wei Chen %A Xin Liu %A Xue Mei %A Yangyou Li %J Pharmaceutical Biology %D 2019 %R https://doi.org/10.1080/13880209.2019.1645701 %X Abstract Context: In China, the herb Sophora tonkinensis Gagnep. (Fabaceae, ST) (Committee of National Pharmacopeia. 2015) exhibits anti-inflammatory, antitumor, and antiviral effects. However, to date, there have been few studies on its gastrointestinal effect. Objective: The gastrointestinal effect of the methanol extract of ST rhizome (STR) was evaluated. Materials and methods: Study was conducted from February to December 2018. In vivo, antidiarrheal activity of STR (125, 250 and 500ˋmg/kg; orally) in castor oil-induced diarrheal mice was studied. In vitro, the effects of STR (0.01每10ˋmg/mL) on the isolated tissue preparations of rabbit jejunum were also investigated, the rabbit jejunum stripes were pre-contracted with Ach (10ˋ5ˋM), K+ (60ˋmM) and tested in the presence of STR, the possible spasmolytic effect was analyzed in the pretreatment of the jejunum preparations with STR or verapamil in Ca2+-free high-K+ (60ˋmM) solution containing EDTA. Results: STR (125, 250 and 500ˋmg/kg) exhibited antidiarrheal activity. STR (0.01每10ˋmg/mL) completely relaxed spontaneously contracting, Ach (10ˋ5ˋM) and high K+ (60ˋmM) induced contracted jejunum with an EC50 value of 0.66 (0.49每0.96), 0.39 (0.28每0.44) and 0.17 (0.10每0.21), similar to verapamil. Concentration每response curves of CaCl2 could be significantly moved to the right and down in the presence of STR (0.3, 1ˋmg/mL). Discussion and conclusions: Results suggest the presence of antidiarrheal activity and spasmolytic effects of STR, possibly mediated through Ca2+ channel blocking activity, providing the pharmacological basis for its traditional uses in gastrointestinal disorders %U https://www.tandfonline.com/doi/full/10.1080/13880209.2019.1645701