Bacterial infection (Legionella pneumophila) stimulates fever, metabolic rate and brown adipose tissue activity in the guinea pig.

The objective of this study was to assess whether bacterial infection stimulates oxygen consumption and brown adipose tissue (BAT) activity. Guinea pigs infected with Legionella pneumophila showed marked fever and a significant (33%) increase in resting oxygen consumption (VO2), 24h after infection. At this time, food intake and body weight were normal and the in vitro thermogenic activity of BAT taken from infected animals was elevated by 64% above that of control guinea pigs. VO2 and BAT activity fell to control values by 48h as infected animals became moribund and over this period food intake was markedly reduced.