Ongoing ingestive behavior is rapidly suppressed by a preabsorptive, intestinal "bitter taste" cue

Area of Science:

• Neuroscience
• Gastroenterology
• Behavioral Science

Background:

• Cells in the gastrointestinal (GI) tract express molecular receptors and signaling components typically associated with taste.
• The function of these post-oral
• taste
• receptors in regulating food intake is of significant interest.

Purpose of the Study:

• To investigate if taste cues within the GI tract are detected by rats.
• To determine if these detected cues can directly influence feeding behavior.
• To establish a model for studying post-oral taste perception.

Main Methods:

• Rats were trained to drink and simultaneously receive intestinal infusions.
• A microbehavioral analysis of intake was employed using lickometers.
• Taste stimuli, including denatonium benzoate (DB) and saccharin, were infused intraduodenally.

Main Results:

• Rats reduced licking behavior when a bitter stimulus (DB) was added to intestinal infusions, indicating a conditioned taste aversion.
• The bitter stimulus accelerated aversion development and improved temporal detection.
• CCK-1R antagonist partially blocked the aversion response to intestinal DB.
• Rats did not alter intake in response to intestinal saccharin infusions.

Conclusions:

• Post-oral taste receptors in the GI tract can detect taste stimuli and influence feeding behavior.
• The developed intestinal taste aversion paradigm is effective for studying gut chemosensation.
• This research provides insights into the role of gut taste receptors in appetite regulation.