Investigation of Protein and Energy Metabolism in Burned Rats and Without Infection

Research Project

Project/Area Number	01570722
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	General surgery
Research Institution	Teikyo University, School of Medicine Trauma and Critical Care Center
Principal Investigator	KOBAYASHI Kunio Teikyo University, School of Medicine, Professor, 医学部, 教授 (80082147)
Co-Investigator(Kenkyū-buntansha)	SUZUKI Hiromasa Teikyo University, School of Medicine, Instructor, 医学部, 助手 (00187759) HASEBE Masaharu Teikyo University, School of Medicine, Assistant Professor, 医学部, 講師 (00082264)
Project Period (FY)	1989 – 1990
Project Status	Completed (Fiscal Year 1990)
Budget Amount *help	¥2,100,000 (Direct Cost: ¥2,100,000) Fiscal Year 1990: ¥400,000 (Direct Cost: ¥400,000) Fiscal Year 1989: ¥1,700,000 (Direct Cost: ¥1,700,000)
Keywords	Burned Rat / Infection (Complication) / Protein and Energy Metabolism / Indirect Calorimetry / Energy Expenditure / LCT (Long-Chain Triglyceride) / MCT (Medium-Chain Triglyceride) / Ketone Bodies / 熱傷感染モデル / エネルギ-基質 / 間接熱量測定 / MCT / ICT
Research Abstract	Utilization of glucose (G), long-chain triglycerides (LCT) and medium-chain triglycerides (MCT) as energy sources were investigated in two different models : burned rat without infection (B-model) and with infection (BI-model). 20% burn was induced in male Sprague-Dawley rats weighing 320-340g. Normal saline was infused for the first 10 hours post-burn. And 10^9 CFU of Staphylococcus aureus was injected subcutaneously into the back of the animals in the BI-model. Both models were divided into 3 groups according to the TPN energy source (G,LCT or MCT), and were given isocaloric (156kcal//kg/day) and isonitrogenous (1gN/kg/day) TPN consisting one of the following : 100% of non-protein calories (NPC) as glucose (group G), 50% of NPC as glucose and 50% of NPC as LCT (group L), 50% of NPC as glucose and 50% of NPC as MCT (group M). After 12 hours of TPN, the animals were artificially ventilated and the energy expenditure (EE) was measured for the following 8 hours using indirect calorimetry … More . At the end of the EE measurement, blood, liver and muscle were harvested for measuring various metabolites. EE in the B-model showed no differences among the three groups ; however, EE in group M(136<plus-minus>6kcal/kg/day) was significantly higher than that in group L(114<plus-minus>2) in the BI-model(p<0.01), indicating greater oxidation of MCT than LCT at the highly stressed condition of bacterial infection. Although was no difference in muscle protein content in the BI-model, in both models urinary nitrogen loss was significantly less in group M than in group G, suggesting a better nitrogen sparing effects of MCT with glucose than glucose alone. In the BI-model, serum total ketone bodies (TKB) were lower in group M(334<plus-minus>49 mumol/L) than in group L(612<plus-minus>96). This is contrast to the B-model where group M(866<plus-minus>82) had the highest TKB among the groups. This indicates an increased utilization of ketone bodies by peripheral tissues during infections complication. All the data suggest that MCT may be a highly oxidized and protein sparing energy source for burn injury specifically complicated with Less