mckemy "et al.", 2002 provided some of the first evidence for existence of a cold-activated receptor throughout the mammalian somatosensory system. using calcium imaging and patch clamp based approaches, they showed a response in dorsal root ganglion (drg) neurons that exposure to cold, 20 °c or cooler, lead to a response in calcium influx. this receptor was shown to respond to both cold temperatures, menthol, and similar now-known agonists of the trpm8 receptor. it works in conjunction with the trpv1 receptor to maintain a feasible threshold temperature range in which our cells are comfortable and our perception of these stimuli occurs at the spinal cord and brain, which integrate signals from different fibers of varying sensitivity to temperature. application of menthol to skin or mucus membranes results directly in membrane depolarization, followed by calcium influx via voltage-dependent calcium channels, providing evidence for the role of trpm8 and other trp receptors to mediate our sensory interaction with the environment in response to cold in the same way as in response to menthol.