TRP channels in the sensation of heat

Abstract

Animals must sense temperature in the external environment in order to find ambient temperatures appropriate for different activities, such as hunting or sleeping, and to avoid even brief exposure to damaging extremes of temperature. They must also sense their internal bodily temperature in order to regulate it. Some members of the TRP channel family are activated by thermal stimuli, and are consequently named the thermoTRPs; thermally sensitive ion channels are also found in the potassium and chloride channel families. When thermoTRP channels are expressed in a sensory neuron, channel opening in response to heat leads to depolarization and generation of action potentials. It is still an open question which channels are important for sensation of thermal stimuli in the external environment, and channels involved in the sensation of internal bodily temperature for the purposes of thermoregulation are even less understood. In this chapter we review the properties of thermosensitive ion channels and their roles in thermosensation and thermoregulation, with an emphasis on TRP channels.