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A Japanese herbal medicine, Dai-Kenchu-To (DKT) is clinically effective in adhesive and paralytic intestinal obstruction. We previously reported that intra-gastric (IG) administration of capsaicin, a major pungent ingredient of chili and known to bind the transient receptor potential cation channel, subfamily V, member 1 (TRPV1), stimulated colonic motility and defecation in dogs. DKT contains several pungent ingredients including dried ginger rhizome and zanthoxylum fruit. Aim of the present study was to investigate the effect of IG DKT on colonic motility and role of TRPV1 in DKT-induced colonic contractions. Methods: Five mongrel dogs were used equipped with strain gauge force transducers at the proximal, middle, and distal colon to measure circular muscle activity. Colonic motility was studied after IG administration of DKT at the dose of 2.5, 5 g dissolved in 70 ml saline via a catheter placed in the proximal stomach in the interdigestive state. To study the role of cholinergic and serotonergic receptors in DKT-induced contractions in the colon, saline as control, muscarinic antagonist atropine (0.1 mg/kg), nicotinic antagonist hexamthonium (5 mg/kg), or serotonin-3 antagonist ondansetron (1 mg/kg), was injected intravenously 5 min before IG administration of DKT (5 g). To study the role of TRPV1, 70 ml saline as control or capsazepine (10 mg) dissolved in 70 ml saline was administered into the stomach 5 min before IG administration of DKT (5 g). Area under the contractile curve for 30 minutes after IG DKT administration was measured and expressed as motility index (MI). Results: IG DKT induced colonic contractions immediately after the administration, and MI increased in a dose-dependent manner along the entire colon. Duration and amplitude of IG DKT-induced colonic contractions did not differ from spontaneously occurring colonic contractions. Pretreatment with atropine and hexamthonium abolished these IG DKT-induced colonic contractions, and MI was decreased along the entire colon compared to control (p<0.05). Ondansetron also inhibited IG DKT-induced colonic contractions and MI was decreased in the proximal, middle, and distal colon compared to control (p<0.05). Capsazepine inhibited IG DKT-induced colonic contractions, and MI at the proximal, middle, and distal colon was decreased compared to control (p<0.05). Conclusions: These results indicate IG administration of DKT stimulates colonic motility via TRPV1, cholinergic, and serotonergic receptors. These effects of DKT might be a mechanism to ameliorate intestinal obstruction.