Behavioral thermoregulation by hypoxic rats

✍ Scribed by Dupré, R. Keith ;Owen, T. Lon

• Book ID: 102895241
• Publisher: John Wiley and Sons
• Year: 1992
• Tongue: English
• Weight: 519 KB
• Volume: 262
• Category: Article
• ISSN: 0022-104X
• DOI: 10.1002/jez.1402620213

✦ Synopsis

Abstract

To address whether a shift in hypothalamic thermal setpoint might be a significant factor in induction of hypoxic hypothermia, behavioral thermoregulation was examined in 7 female Sprague‐Dawley rats implanted with radiotelethermometers for deep body temperature (T~b~) measurement in a thermocline during normoxia (PO~2~ = 125 torr) and hypoxia (PO~2~ = 60 torr). Normoxic rats (T~Nox~) selected a mean ambient temperature of 19.7 ± 1.4 (SE) °C and maintained T~b~ at 37.0 ± 0.2°C. Hypoxic rats selected a significantly higher ambient temperature (T~Hox~ = 28.6 ± 2.2°C) but maintained T~b~ significantly lower at 35.5 ± 0.3°C. Without a thermal gradient (ambient temperature = 25°C), T~b~ during hypoxia was 35.4 ± 0.4°C. The maintenance of a lower body temperature during hypoxia through behavioral thermoregulation despite having warmer temperatures available supports the hypothesis that the thermoregulatory setpoint of hypoxic rats is shifted to promote thermoregulation at a lower T~b~, effectively reducing oxygen demand when oxygen supply is limited. © 1992 Wiley‐Liss, Inc.