A U.S. study identified a brain pathway in rodents that could be used in treatments to quit smoking without gaining weight, researchers say. Senior author Dr. Marina Picciotto of Yale University in New Haven, Conn., and colleagues uncovered a specific subclass of brain nicotinic receptor involved in nicotine\'s ability to reduce food intake in rodents. The study, published in Science, found that a nicotine-like drug, cytisine, specifically activated nicotinic receptors in the hypothalamus a part of the brain center that controls feeding resulting in the activation of a circuit that reduced food intake and body fat in a mouse model. Picciotto says the effect was very specific, since a drug that prevented cytisine from binding to its hypothalamic receptors blocked the reduction in food intake. \"These mouse models allow us to explore the mechanisms through which nicotine acts in the brain to reduce food intake,\" Picciotto says in a statement. \"We found that nicotine reduced eating and body fat through receptors implicated in nicotine aversion and withdrawal rather than reward and reinforcement.\"