METABOLIC INFLUENCES ON SATIETY IN RATS RECEIVING PARENTERAL-NUTRITION

Metabolic influences on satiety in rats receiving parenteral nutrition . Am. J. Physiol. 266 (Regulatory Integrative Comp. Physiol. 35): R381 -R386, 1994. - Food intake is reduced during parenteral nutrition (PN) proportionally to the amount of calories or composition of the soluti on infused. The relative importance of infused glucose and lipid, 50 a nd 30% of PN kilocalories, respectively, in reducing food intake durin g PN was examined. Glycolysis, fatty acid oxidation, or both were acut ely disrupted with 2-deoxy-D-glucose (2-DG) and mercaptoacetate (MA). Rats receiving intravenous infusions of saline or a PN solution provid ing 100% of total daily calories (PN-100) received a single intraperit oneal injection of saline, 2-DG, and/or MA during the early light phas e. 2-DG (1.4 or 2.2 mmol/kg) did not initiate feeding in PN-100 rats, although hyperglycemia was evident in all rats 1 h after 2-DG. Food in take of PN-100 rats after MA (0.4 mmol/kg) was similar to 50% that of control rats. When 2-DG (1.4 mmol/kg) and MA (0.4 mmol/kg) were admini stered concomitantly, PN-100 and control rats consumed the same amount of food. During PN-100, rats appeared to be more sensitive to losing metabolic energy derived from lipid than from glucose.