Intermittent access to a sucrose solution for rats causes long-term increases in consumption

Area of Science:

• Behavioral neuroscience
• Animal models of eating behavior

Background:

• Intermittent access to palatable foods can lead to overconsumption.
• Understanding the factors influencing food intake is crucial for metabolic health research.

Purpose of the Study:

• To investigate how intermittent access to sucrose solutions affects consumption patterns in adult male rats.
• To determine if established consumption differences are maintained when access schedules are altered.

Main Methods:

• Adult male rats were given continuous or intermittent (every 2nd, 3rd, or 4th day) access to 4% sucrose solution over 49 days.
• A subsequent phase involved alternate-day access for all rats to assess maintenance of consumption differences.
• Lick-by-lick analysis was used to examine meal patterns and satiety.

Main Results:

• Intermittent sucrose access significantly elevated daily sucrose consumption compared to continuous access.
• Consumption differences established in Phase I were maintained in Phase II.
• Rats consumed larger meals, not more frequent meals, during intermittent access, suggesting altered satiety.

Conclusions:

• Intermittent access to palatable foods, such as sucrose, robustly increases consumption in rats.
• Altered satiety mechanisms, rather than increased meal frequency, appear to drive higher intake under intermittent access conditions.
• These findings have implications for understanding overeating and obesity.