ABSTRACT
BACKGROUND/AIMS: The gastrointestinal motility effects of endogenous incretin hormones enhanced by dipeptidyl peptidase-IV (DPP-IV) inhibitors have not yet been sufficiently investigated. The aim of this study was to determine whether single pre-prandial sitagliptin, the DPP-IV inhibitor, administration might have an effect on the rate of liquid gastric emptying using the 13C-acetic acid breath test. METHODS: Ten healthy male volunteers participated in this randomized, two-way crossover study. The subjects fasted for overnight and were randomly assigned to receive 50 mg sitagliptin 2 hours before ingestion of the liquid test meal (200 kcal per 200 mL, containing 100 mg 13C-acetate) or the test meal alone. Under both conditions, breath samples were collected for 150 minutes following the meal. Liquid gastric emptying was estimated by the values of the following parameters: the time required for 50% emptying of the labeled meal (T1/2), the analog to the scintigraphy lag time for 10% emptying of the labeled meal (Tlag), the gastric emptying coefficient and the regression-estimated constants (beta and kappa), calculated by using the 13CO2 breath excretion curve using the conventional formulae. The parameters between the 2 test conditions were compared statistically. RESULTS: No significant differences in the calculated parameters, including T1/2, Tlag, gastric emptying coefficient or beta and kappa, were observed between the 2 test conditions. CONCLUSIONS: The present study revealed that single-dose sitagliptin intake had no significant influence on the rate of liquid gastric emptying in asymptomatic volunteers.