Calorie restricted rats do not increase metabolic rate post-LPS, but do seek out warmer ambient temperatures to behaviourally induce a fever.

摘要: Abstract Due to previous work where we have demonstrated attenuated febrile responses post-lipopolysaccharide (LPS) in calorie restricted (CR) rodents aimed explore metabolic rate and behavioral thermoregulation these CR animals post-LPS. Male Sprague–Dawley rats fed ad libitum (AL) or 50% (CR50%) of the AL animals' food intake for 28 days were injected on 29th day with 50 μg/kg LPS. Core body temperature (Tb), self-selected ambient (Ta), indirect calorimetry [to determine energy expenditure (EE) respiratory quotient (RQ)] measured 8 hours The chose sit at a higher Ta (28.1 ± 0.4 °C) compared (23.7 ± 1.4 °C) baseline warmer from 30 min until 420 min post-LPS; however, selected only 270 min Tb 120, 150, 240 480 min In contrast our findings also most time between 270 When allowed select do so thereby mount response, although significantly delayed shorter-lived. experiment an elevated 150 fever profile was attenuated, increase occurring Indirect indicated that reduced EE (− 17.9% ± 1.3) baseline. After LPS, multiple points 90 420 min, whereas no change observed rats. similar profiles RQ after LPS decrease their 360, 450, 480 min, difference. cost during period low availability may outweigh benefits producing response relatively small dose