Non-invasive Method for Evaluation of Gastrocecal Transit Time by Using a Breath Test in Conscious Rats

Abstract

The aim of this study was to establish a method for evaluating gastrocecal transit time using a simple and noninvasive ¹³C breath-test system in conscious rats. After fasting, rats were orally administered lactose-[¹³C]ureide. ¹³CO₂ level in the expired air was measured at appropriate intervals. It was confirmed that priming dose of lactose-ureide was necessary for determining gastrocecal transit time. The level of ¹³CO₂ in the expired air increased in a lactose-[¹³C]ureide dose–dependent manner. The gastrocecal transit time determined with 30 mg/kg of lactose-[¹³C]ureide was 160 ± 24.5 min. This method is expected to contribute to the further understanding of intestinal pathophysiology.