SLC6A3 and obesity due to melanocortin 4 receptor deficiency: Although we did not observe any differences in food and fluid intake between treatment groups, it would be important in future to expose stevia-fed rats to a palatable, high-fat diet to examine if they have a greater propensity to increase food intake, develop obesity, and decrease physical activity as a result of altered TH and DAT gene expression in the nucleus accumbens.