Inside the well-protected and well-ventilated human skull, the temperature of a few hundred thousand neurons can deviate by several degrees centigrade from that of the surrounding 100 billion or so cells. These cells constitute around 15% of the neurons in the brain's preoptic area (POA) and can change their firing rate dramatically upon a 1° to 3°C change in local temperature (1). Astoundingly, this change in activity can alter the body's core temperature. Cellular and molecular details of the warm and cold sensitivity of these neurons are not well understood. Although the induction of fever has been well studied, the mechanisms that terminate fever are not yet clear. On page 1393 of this issue, Song et al. (2) report that a transient receptor potential (TRP) cation channel (3, 4) is key to the function of these neurons in thermoregulation, particularly in response to fever.
Author: Tamas Bartfai