MACRONUTRIENT SELECTION FOLLOWING 2-DEOXY-D-GLUCOSE AND MERCAPTOACETATE ADMINISTRATION IN RATS

Mercaptoacetate (MA) and 2-deoxy-D-glucose (2-DG), which block fatty a cid oxidation and glucose utilization respectively, were injected in r ats that were maintained on a macronutrient self-selection diet consis ting of separate jars of carbohydrate, protein, and fat. Rats were div ided into two groups based on their baseline preference for carbohydra te or fat. MA increased intake of carbohydrate and protein and decreas ed intake of fat regardless of the rats' baseline preference. 2-DG inc reased intake of carbohydrate in rats regardless of baseline preferenc e. 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, where as MA treated rats did not. When protein was the only macronutrient so urce available, both 2-DG and MA treated rats increased protein intake . MA increases the intake of nutrients which can be utilized by periph eral tissues except fat, which is not being oxidized. 2-DG increases t he intake of carbohydrate which may be necessary to overcome the centr al glucoprivation caused by this drug. (C) 1998 Elsevier Science Inc.