Localisation of TRP Channels in Mammalian Skin

Abstract: Perception of temperature in mammals is critical for their survival, it enables them to perceive the world around them and act with an appropriate physiological or behavioural response. However, the full understanding of the thermosensory system in mammals has thus far been clouded. TRP channels are thermally sensitive and are known to associate with heat sensitive nerve fibers and keratinocytes in the skin. In my study the focus was understanding their thermotransduction in the rhinarium tissue and whether the sensitivity to radiating heat can be improved by keeping the rhinarium at lower temperatures (as observed in dogs). To solve this I attempted to localise TRPV1-4 and TRPM8, using immunohistochemistry, in the dog and bear rhinarium and compared the expression to other tissue types (belly). My results supported a bolometer like system, consisting of superficial TRP channel skin receptors (TRPV2, TRPV4 and TRPM8) and deep TRP channel skin receptors (all five channels). This would indicate that a colder nose would increase sensitivity to radiating heat whilst protecting the rhinarium from noxious heat.