Cross-species comparison: imaging and mapping gastric motor functions in humans and rats using contrast-enhanced rapid MRI

Motivation: Direct and granular cross-species comparisons of gastric motor functions remain scarce in the literature. Goal(s): This study aims to establish functional similarities and distinctions of the stomach between humans and rats, and lay the foundation for integrating preclinical findings into clinical gastrointestinal studies. Approach: Using comparable MRI protocols, we examined the interspecies parallels and distinctions in their functions as pressure and peristaltic pumps. Results: Similarities were confirmed with high-resolution spatial maps, including intragastric pressure gradient and spatial distribution of peristaltic amplitude and frequency, despite their differences in scale. We highlighted the pronounced variance in initialization and spatial coordination of peristaltic contractions across species. Impact: This work serves as the first one to map and compare gastric motor events with comparable MRI protocols, laying the foundation for preclinical rat research to clinical translation using contrast-enhanced gastrointestinal MRI.