title: 13C-acetic acid is more sensitive than 13C-octanoic acid for evaluating gastric emptying of liquid enteral nutrient formula by breath test in conscious rats.
abstract: Breath test using 13C-labeled compound has been used as a convenient method to evaluate gastric emptying. 13C-Labeled acetic acid or octanoic acid has been used in clinic. However, there is few report comparing two compounds. This study aimed to compare 13C-acetic acid and 13C-octanoic acid in newly-constituted breath test for monitoring gastric emptying in conscious rats. After fasting, rats were orally administered Racol (liquid enteral nutrient formula) containing 13C-labeled compound (same molar of 13C-acetic acid or 13C-octanoic acid) and housed in a chamber. The expired air in the chamber was collected in a breath-sampling bag using a tube and aspiration pump. The level of 13CO2 in the expired air was measured using an infrared spectrometer at appropriate intervals for 120 min. Expired 13CO2 air from 13C-acetic acid changed at significantly higher levels than that from 13C-octanoic acid. Cmax and AUC120 min values of expired 13CO2 from 13C-acetic acid were significantly higher than those from 13C-octanoic acid, but Tmax was not different between them. These results show that 13C-acetic acid is more sensitive for monitoring gastric emptying than 13C-octanoic acid in liquid test meal although both acids clearly monitored gastric emptying.
authors.affiliation: Food Science Institute, Division of Research and Development, Meiji Dairies Corporation, 540 Naruda, Odawara, Kanagawa 250-0862, Japan. masayuki_uchida@meiji-milk.com
authors.forename: Masayuki
authors.initials: M
authors.lastname: Uchida
authors.forename: Kimiko
authors.initials: K
authors.lastname: Shimizu
mesh_terms: D019342:Acetic Acid / Q000008:administration & dosage* / Q000378:metabolism / Q000493:pharmacokinetics; D000284:Administration, Oral; D000818:Animals; D019540:Area Under Curve; D001944:Breath Tests / Q000295:instrumentation / Q000379:methods; D002210:Caprylates / Q000008:administration & dosage* / Q000378:metabolism / Q000493:pharmacokinetics; D002247:Carbon Isotopes; D003243:Consciousness; D004750:Enteral Nutrition; D005746:Gastric Emptying / Q000502:physiology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D013055:Spectrophotometry, Infrared
chemical_list: D002210:Caprylates; D002247:Carbon Isotopes; C031492:octanoic acid; D019342:Acetic Acid