Background: The herbal medicine Dai-Kenchu-To, composed of zanthoxylum fruit, ginseng root, and dried ginger rhizome, is clinically effective for uncomplicated postoperative adhesive intestinal obstruction. We investigated the effect of Dai-Kenchu-To and each ingredient on upper gastrointestinal motility and its mechanism of action.
Methods: Five mongrel dogs were equipped with 4-strain gauge-force transducers on the gastric body, antrum, duodenum, and jejunum to measure contractile activity of the circular muscle. Dai-Kenchu-To (1.5 g) or the separate ingredients zanthoxylum fruit, ginseng root, or dried ginger rhizome (1.0 g each) were administered by bolus into the gastric lumen. The effect of atropine, hexamethonium, phentolamine, propranolol, and ondansetron on intragastric Dai-Kenchu-To-induced contractions was studied.
Results: Intragastric Dai-Kenchu-To induced phasic contractions in the antrum, duodenum, and jejunum. Zanthoxylum fruit elicited phasic contractions mainly in the duodenum and jejunum, whereas dried ginger rhizome induced phasic contractions in the antrum. Ginseng root had no effect. Phasic contractions induced by intragastric Dai-Kenchu-To were inhibited by atropine and hexamethonium at all sites, although ondansetron inhibited these contractions in the antrum and duodenum.
Conclusions: Intragastric Dai-Kenchu-To stimulates upper gastrointestinal motility through cholinergic and 5-hydroxytryptamine 3 receptors.