Brain temperature measurement and regulation in awake and freely moving rodents

Temperature measurement and control are essential in most ischemia experiments. Hypothermia lessens ischemic brain injury whereas hyperthermia exacerbates it. A substantial number of ischemia studies rely solely on rectal temperature measurements during the insult. However, rectal temperature may not accurately reflect brain temperature especially during global ischemia. Furthermore, postischemic temperature changes are often inadequately monitored. Delayed cooling reduces injury, whereas delayed hyperthermia aggravates it. This review summarizes our experiences with core and brain telemetry probes to continually measure temperature in various ischemia models. Furthermore, we discuss methods to simultaneously measure and regulate temperature in the freely moving postischemic rodent, and the need for such control in ischemia research. (C) 2003 Elsevier Science (USA). All rights reserved.