以山莓叶醇提物（RE）和对羟基肉桂酸乙酯（EC，活性跟踪分离到的山莓叶中活性较强的物质）为材料，以兔离体肠运动为模型，研究了RE和EC抑制肠管运动的剂量效应，同时考察了RE和EC分别与抗腹泻相关的4个关键通道的4种致痉剂（乙酰胆碱、酚妥拉明、组胺和氯化钡）对肠管运动的影响。结果表明：RE浓度为1~10 mg/mL范围内，肠管的张力增量变化率（TVP）均为30%以上，且RE浓度为4 mg/mL时，TVP达到45.37%；浓度10~800 μg/mL范围内，EC对肠管运动的抑制作用均极显著高于阿托品（P<0.01），且EC浓度为400 μg/mL时，TVP达到最大（70.45%）；RE主要通过作用于乙酰胆碱通道胆碱能M受体和组胺通道来抑制肠管运动；EC主要通过作用于肾上腺素α受体、组胺通道和钙离子通道来抑制肠管运动。因此，RE和EC是抗腹泻的高效的多靶点药物，且RE中的EC的抗腹泻效果极显著优于阿托品。

Ethyl p-coumarate (EC), a compound with a relatively strong activity was extracted from Rubus corchorifolius leaves by bioactivity-guided isolation. Dose responses of Rubus corchorifolius leaf extract (RE) and EC for inhibition of intestinal movement were studied in terms of movement of isolated rabbit intestine model. The effects of RE and EC as well as four spasmogenic agents (acetylcholine, phentolamine, histamine, and barium chloride) that are related to four key channels in antidiarrheal effects on the movement of isolated intestine were also investigated. The results showed that the tensional variation percentage (TVP) of intestine was above 30% when RE concentration was in the range of 1 to 10 mg/mL and reached maximum (45.37%) at 4 mg/mL. When the concentration of EC was in the range of 10 to 800 μg/mL, the inhibitory effect on intestinal movement was significantly higher than that of atropine (p < 0.01) at the same concentration and TVP value reached the maximum (70.45%) when the concentration of EC was 400 μg/mL. Thus, the inhibition of intestinal movement by RE was mainly achieved through its effects on the cholinergic M receptor of acetylcholine and histamine channels, whereas that by EC was mainly achieved through its effects on the adrenergic a-receptor, histamine channel, and calcium ion channel. Therefore, RE and EC act on different targets and are effective antidiarrheal drugs, where EC in RE exerts a significantly stronger effect than atropine.

广东省科技计划农业公关项目（2012A020602038）；高等学校博士学科点专项科研基金联合资助课题（20114404120022）