Dietary Agonists of TRPV1 Inhibit Gastric Acid Secretion in Mice

• Published in: Planta medica Vol. 78; no. 17; pp. 1801 - 1806
• Main Authors: Okumi, Hirokuni, Tashima, Kimihito, Matsumoto, Kenjiro, Namiki, Takao, Terasawa, Katsutoshi, Horie, Syunji
• Format: Journal Article
• Language: English
• Published: Germany 01.11.2012
• Subjects: acute effects; additive effect; Administration, Oral; agonists; Animals; antagonists; capsaicin; Capsaicin - administration & dosage; Capsaicin - pharmacology; Capsicum - chemistry; Catechols - administration & dosage; Catechols - pharmacology; Dose-Response Relationship, Drug; Drug Synergism; Drug Therapy, Combination; Fatty Alcohols - administration & dosage; Fatty Alcohols - pharmacology; gastric acid; Gastric Acid - metabolism; Gastric Mucosa - drug effects; ginger; hot peppers; Male; Mice; nerve fibers; oral administration; Plant Extracts - pharmacology; pylorus; rats; secretion; TRPV Cation Channels - agonists; Zingiber officinale - chemistry
• ISSN: 0032-0943; 1439-0221
• DOI: 10.1055/s-0032-1315387

Capsaicin and 6-gingerol, pungent components of chilli pepper and ginger, are known as dietary agonists of transient receptor potential vanilloid-1. Transient receptor potential vanilloid-1 nerve fibers are recognized to play a role in gastric mucosal integrity in rats. In the present studies, we examined the acute effects of peroral administration of capsaicin and 6-gingerol on gastric acid secretion in conscious mice. These agents were given p. o. 30 min before the pylorus was ligated. Oral administration of capsaicin (1.0-100 mg/kg) or 6-gingerol (1.5-50 mg/kg) significantly and dose-dependently inhibited basal acid secretion. Pretreatment with BCTC, a transient receptor potential vanilloid-1 antagonist, significantly reversed the reduced basal acid secretion by capsaicin or 6-gingerol. The combination of the lowest doses of capsaicin and 6-gingerol markedly inhibited basal acid secretion in conscious mice and this was also significantly reversed by BCTC. Moreover, the combination of the maximal dose of capsaicin and 6-gingerol inhibited basal acid secretion only to the level of a single administration of the maximal dose of capsaicin. These results suggest that the combination of capsaicin and 6-gingerol has an additive effect on the inhibition of gastric acid secretion through activation of transient receptor potential vanilloid-1. In separate experiments, intraduodenal administration of either capsaicin (30 mg/kg) or 6-gingerol (15 mg/kg), whose doses were observed to have a significant inhibitory effect by oral administration, tended to inhibit basal acid secretion compared with the vehicle. These results suggest that the combination of capsaicin and 6-gingerol has an additive effect on inhibition of gastric acid secretion through activation of transient receptor potential vanilloid-1, and oral administration of transient receptor potential vanilloid-1 agonists directly stimulates transient receptor potential vanilloid-1 in the gastric lumen, resulting in a potent reduction of gastric acid secretion.