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Updated: Jul 17, 2026
07:37
Roux-en-Y Gastric Bypass Operation in Rats
Published on: June 11, 2012
Summary
This study investigated how fat exits the stomach. Most intracellular fat (ICF) leaves bound to solid food particles, while extracellular fat (ECF) primarily exits as an oil phase.
Area of Science:
- Gastroenterology
- Digestive Physiology
- Nutrient Absorption
Background:
- Understanding gastric emptying is crucial for digestive health.
- The fate of dietary fat during gastric transit remains incompletely understood.
- Distinguishing between intracellular fat (ICF) and extracellular fat (ECF) is key to elucidating fat digestion.
Purpose of the Study:
- To determine if fat leaves the stomach within or attached to solid food particles.
- To differentiate the gastric emptying patterns of aqueous, solid, ECF, and ICF phases of a meal.
- To investigate species-specific differences in fat gastric emptying.
Main Methods:
- Gastric emptying of fat was studied in 6 human subjects and 6 dogs.
- Dogs utilized Roux-en-Y duodenojejunostomies for direct chyme collection.
- Humans were studied using a duodenal multilumen tube to track phase-specific markers.
Main Results:
- The aqueous phase emptied rapidly in both species.
- Solid, ECF, and ICF phases emptied in parallel after an initial lag.
- In humans, 51% of ICF and 22% of ECF emptied with solid particles. In dogs, 66% of ICF and 13% of ECF emptied with solids.
Conclusions:
- Most intracellular fat (ICF) empties from the stomach attached to solid food particles.
- The majority of extracellular fat (ECF) empties as an oil phase, separate from solids.
- These findings clarify the distinct gastric transit mechanisms for different fat components.
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