Diet-induced obesity: dopamine transporter function, impulsivity and motivation

摘要: A rat model of diet-induced obesity (DIO) was used to determine dopamine transporter (DAT) function, impulsivity and motivation as neurobehavioral outcomes predictors obesity. To evaluate alterations following the development DIO induced by an 8-week high-fat diet (HF) exposure, striatal D2-receptor density, DAT function expression, extracellular concentrations, impulsivity, for high- low-fat reinforcers were determined. DIO, antecedents including reinforcers, evaluated before HF exposure. Striatal density determined in vitro kinetic analysis [3H]raclopride binding. using [3H]dopamine uptake, methamphetamine-evoked overflow no-net flux vivo microdialysis. cell-surface expression biotinylation western blotting. Impulsivity food-motivated behavior a delay discounting task progressive ratio schedule, respectively. Relative obesity-resistant (OR) rats, obesity-prone (OP) rats exhibited 18% greater body weight HF-diet 42% lower 30% total 40% 45% twofold overflow. OP higher food, surprisingly, less impulsive relative OR rats. Impulsivity, concentration did not predict DIO. Importantly, predicted Human studies are limited their ability if causes or consequences The current animal shows that but behavior, predicts obesity, whereas decreases only after