The researchers tested how a hormone called PYY(3-36) affects rats' food intake and taste preferences. They found that different doses of PYY(3-36) caused rats to eat less and avoid certain foods. Lower doses reduced food intake without causing aversion, while higher doses made rats avoid the food they were given. This suggests that PYY(3-36) can make rats feel sick at higher doses. The hormone works by slowing down the emptying of the stomach, which can lead to a dislike of certain foods.