Bead study: a novel method to measure gastrointestinal transit in mice

Area of Science:

• Gastroenterology
• Medical Imaging
• Animal Models

Background:

• Current mouse intestinal transit assessment methods are time-consuming or require animal euthanasia.
• A novel in vivo method adapting a clinical 'shapes study' was developed for mice.

Purpose of the Study:

• To develop and validate a novel in vivo method for assessing gastrointestinal (GI) transit in mice.
• To compare the accuracy of the novel in vivo method with traditional postmortem analysis.

Main Methods:

• Mice (n=70) were gavaged with steel beads and barium, followed by short videofluoroscopy.
• In vivo and postmortem GI tract analyses were performed to localize beads.
• Correlation between in vivo and postmortem scoring was assessed, and changes after drug treatment were evaluated.

Main Results:

• Barium effectively outlined the stomach and cecum as reference points.
• Excellent correlation (r=0.93) was found between in vivo and postmortem GI transit scores.
• The method detected significant changes in GI transit after loperamide and prucalopride administration.

Conclusions:

• Videofluoroscopy reliably localizes metallic beads within the mouse GI tract in vivo.
• This novel method enables repetitive, non-invasive GI transit measurements in mice.
• The technique is sensitive to changes induced by motility-modifying agents.