title: Energy expenditure in rats maintained with intravenous or intragastric infusion of total parenteral nutrition solutions containing medium- or long-chain triglyceride emulsions.
abstract: Energy expenditure was determined in male Fischer 344 rats (235-246 g) fed by intravenous (IV) or intragastric (IG) infusion with total parenteral nutrition solutions providing 65% of nonprotein energy as fat from long-chain triglyceride (LCT) or a 3:1 admixture of medium-chain triglyceride (MCT) and LCT emulsions. Respiratory gas exchange and somatomotor activity were assessed continuously for 24 h during d 5 and 11 of infusion feeding. The MCT infusion resulted in one-third the weight gain noted with LCT infusion (MCT, 10 +/- 2 g/14 d; LCT, 32 +/- 4 g/14 d; P less than 0.0001). Insulin concentration was 60% higher with IV than with IG infusion and approximately 100% higher with IV-MCT than with IG-MCT or LCT infusion (P less than 0.05). Rats receiving IV infusion of MCT displayed similar levels of motor activity but 8-13% greater daily energy expenditure (kJ.kg-0.75.kJ intake-1) than rats receiving IG-MCT or LCT infusion (P less than 0.05). The MCT infusion also resulted in an elevation in respiratory quotient after cessation of nutrient infusion (MCT, 0.87-0.92; LCT, 0.83-0.85; P less than 0.05). Total and resting energy expenditure decreased approximately 13% from 5 to 11 d of infusion feeding. The lower weight gain and greater energy expenditure seen with MCT- compared with LCT-supplemented total parenteral nutrition may be mediated by higher insulin concentrations.
authors.affiliation: Department of Nutritional Sciences, University of Wisconsin, Madison 53706.
authors.forename: J B
authors.initials: JB
authors.lastname: Lasekan
authors.forename: J
authors.initials: J
authors.lastname: Rivera
authors.forename: M D
authors.initials: MD
authors.lastname: Hirvonen
authors.forename: R E
authors.initials: RE
authors.lastname: Keesey
authors.forename: D M
authors.initials: DM
authors.lastname: Ney
mesh_terms: D000818:Animals; D002153:Calorimetry, Indirect; D004734:Energy Metabolism; D005217:Fat Emulsions, Intravenous / Q000008:administration & dosage; D007262:Infusions, Intravenous; D007263:Infusions, Parenteral; D008297:Male; D009043:Motor Activity; D010101:Oxygen Consumption; D010289:Parenteral Nutrition, Total / Q000379:methods*; D011659:Pulmonary Gas Exchange; D051381:Rats; D011916:Rats, Inbred F344; D014280:Triglycerides / Q000008:administration & dosage* / Q000378:metabolism
chemical_list: D005217:Fat Emulsions, Intravenous; D014280:Triglycerides