Rats normally eat about 85% of their food at night. Lactation increases food intake 3- to 4-fold, but the diurnal pattern of food intake persists. The mechanisms responsible for the diurnal and lactation-induced changes in food intake are still unresolved, hence we have further investigated the possible roles of serum leptin and hypothalamic expression of neuropeptide Y (NPY), agouti-related pe...

Among polygenic mouse models of obesity, the New Zealand obese (NZO) mouse exhibits the most severe phenotype, with fat depots exceeding 40% of total body weight at the age of 6 mo. Here we dissected the components of energy balance including feeding behavior, locomotor activity, energy expenditure, and thermogenesis compared with the related lean New Zealand black (NZB) and obese B6.V-Lep(ob)/...

OBJECTIVE Food intake is highly regulated by central homeostatic and hedonic mechanisms in response to peripheral and environmental cues. Neutral energy balance stems from proper integration of homeostatic signals with those "sensing" the rewarding properties of food. Impairments in brain insulin signaling causes dysregulation of feeding behaviors and, as a consequence, hyperphagia. Here, we so...