Macronutrient selection following 2-deoxy-D-glucose and mercaptoacetate administration in rats

Mercaptoacetate (MA) and 2-deoxy-D-glucose (2-DG), which block fatty acid oxidation and glucose utilization respectively, were injected in rats that were maintained on a macronutrient self-selection diet consisting of separate jars of carbohydrate, protein, and fat. Rats were divided into two groups based on their baseline preference for carbohydrate or fat. MA increased intake of carbohydrate and protein and decreased intake of fat regardless of the rats' baseline preference. 2-DG increased intake of carbohydrate in rats regardless of baseline preference. Protein and fat intakes were not changed after 2-DG administration. If fat was the only macronutrient source available, 2-DG treated rats consumed significantly more fat compared to the saline control, whereas MA treated rats did not. When protein was the only macronutrient source available, both 2-DG and MA treated rats increased protein intake. MA increases the intake of nutrients which can be utilized by peripheral tissues except fat, which is not being oxidized. 2-DG increases the intake of carbohydrate which may be necessary to overcome the central glucoprivation caused by this drug. (C) 1998 Elsevier Science Inc.