They further demonstrated that while insulin injection in the amygdala does not activate insulin signaling and reduce food intake in diet-induced obese rats, an oral administration of PBA (inhibitor of ER stress) for 7 days is able to substantially reduce ER stress, food intake, and increase insulin signaling in the amygdala, suggesting that ER stress may precede and contribute to the development of insulin resistance in the amygdala in a setting of nutrient surplus. This evidence concerns the gene INS and Endoplasmic Reticulum Stress.