Metabolic changes in rats during a continuous infusion of recombinant interleukin-1

• Published in: The American journal of physiology Vol. 270; no. 2 Pt 1; pp. E305 - E312
• Main Authors: Ling, P R, Schwartz, J H, Jeevanandam, M, Gauldie, J, Bistrian, B R
• Format: Journal Article
• Language: English
• Published: United States 01-02-1996
• Subjects: Acute-Phase Proteins - metabolism; Animals; Body Temperature - drug effects; Body Weight - drug effects; Eating - drug effects; Energy Metabolism - drug effects; Fasting; Humans; Hydroxyproline - urine; Interleukin-1 - pharmacology; Interleukin-6 - blood; Kinetics; Male; Methylhistidines - urine; Nitrogen - urine; Proteins - metabolism; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Reference Values
• ISSN: 0002-9513
• DOI: 10.1152/ajpendo.1996.270.2.e305

The effects of recombinant interleukin-1 (IL-1), given as a continuous infusion for 6 days, on host responses were determined in rats. The development of fever, change in food intake and body weight, and key components of the acute-phase response in energy and protein metabolism were assessed. The effects of IL-1 were compared with those observed in a matched pair-fed group (semistarved), to distinguish the contribution from anorexia, and in a group that received IL-1 for 4 h acutely. IL-1 significantly increased core temperature, plasma levels of IL-6, and acute-phase protein production and decreased food intake and the circulating zinc level. The catabolic effects of IL-1 on nitrogen loss and muscle protein breakdown were independent of, and additive to those from malnutrition. The changes in energy expenditure, cumulative urinary nitrogen, and hydroxyproline excretion in the chronic IL-1 group were increased over semistarved animals. Finally, changes in muscle protein kinetics were only seen with chronic IL-1 infusion, and the changes in acute-phase protein were greater.