Decrease in sweet taste in rats after gastric bypass surgery

The literature contains evidence that Roux-en-Y gastric bypass (RYGB) surgery has an effect in humans on taste and preference for carbohydrate-rich foods. This study tested the hypothesis that RYGB affects sweet taste behavior using a rat model. Male Sprague-Dawley rats underwent either RYGB or sham surgery. Then 4 weeks after surgery, the rats were given taste-salient, brief-access lick tests with a series of sucrose concentrations. The RYGB rats, but not the sham rats, lost weight over the 5-week postoperative period. The RYGB rats showed a significant decrease in mean licks for the highest concentration of sucrose (0.25-1.0 mol/l) but not for the low concentrations of sucrose or water. The findings showed that RYGB surgery affected sweet taste behavior in rats, with postsurgical rats having lower sensitivity or avidity for sucrose than sham-treated control rats. This finding is similar to human reports that sweet taste and preferences for high-caloric foods are altered after bypass surgery.