Abstract: To study the effects of the Lepidiumlatifolium L. extracts on rats with gastrointestinal motility disorder and explore its mechanism, 24 SPF SD rats weighing 180~200 g were randomly divided into blank group, model group and test drug group. Each group had 8 rats and the ratio of male to female is 1:1. Each group was given the corresponding drugs by intragastric administration. Each rat in the test drug group was intragastrically administered with 2 mL solution of the extract from Lepidiumlatifolium L. （0.36 g·mL^-1）. Each rat in the blank group and the model group was intragastrically administrated with equal volume of distilled water. After intragastric administration once a day for 6 days, the rats were fasted for 24 h but free of water. on the 7th day, 1 h after the normal administration, the model group and the test group were intraperitoneally injected with atropine sulfate of 2 mg·kg^-1, and the blank group was intraperitoneally injected with the same volume of normal saline. After 20 min, all rats were intragastrically administered with 0.4 ml of 2% blue dextran-2000 solution. After 30 min, rats were anesthetized with 4 mL·kg^-1 of 10% chloral hydrate. The detect index included gastric emptying rate, small intestinal propulsion rate, the substance P （SP） and ghrelin concentrations in gastric and duodenal homogenate by ELISA. The results showed that the gastric emptying rate and small intestinal propulsion rate in the model group were extremely significant lower than those in blank group（P<0.01） while the gastric and duodenal SP concentrations and the gastric ghrelin concentration presented no significant difference （P>0.05）, and the concentration of duodenal ghrelin was significantly higher （P< 0.01）. Compared with the model group, gastric emptying rate and small intestinal propulsion rate in the test drug group were also significantly increased （P<0.01）, and the concentration of SP in gastric was significantly increased （P< 0.05）; the concentration of ghrelin in gastric and the concentration of SP, ghrelin in duodenal were significantly elevated （P< 0.01）. It indicated that the extracts from Lepidiumlatifolium L. might improve the gastrointestinal motility of rats with gastrointestinal motility disorder induced by atropine sulfate by increasing the concentration of SP and ghrelin in the stomach and duodenum.

Key words: Lepidium latifolium L., rats gastrointestinal motility, substance P（SP）, ghrelin