The HFD and LFD used in this report have been described in detail in previous publications (Dourmashkin et al., 2006; Leibowitz et al., 2004). The constituents of the LFD were fat from 10% vegetable oil, carbohydrate from 30% dextrin, 30% cornstarch (ICN Pharmaceuticals), and 40% sucrose (Domino), and protein from casein (Bioserv, Frenchtown, NJ) and 0.03% L-cysteine hydrochloride (ICN Pharmaceuticals). The constituents of the HFD were fat from 75% lard (Armour) and 25% vegetable oil (Crisco), carbohydrate from 30% dextrin, 30% cornstarch (ICN Pharmaceuticals), and 40% sucrose (Domino), and protein from casein (Bioserv) and 0.03% L-cysteine hydrochloride (ICN Pharmaceuticals). These solid diets were supplemented with minerals (USP XIV Salt Mixture Briggs; ICN Pharmaceuticals) and vitamins (Vitamin Diet Fortification Mixture; ICN Pharmaceuticals). The macronutrient composition of these diets was calculated as percentage of total kcal, with the LFD containing 10% fat, 65% carbohydrate, and 25% protein (3.8 kcal/g) and the HFD containing 50% fat, 25% carbohydrate, and 25% protein (5.2 kcal/g).
