Ion channels of cold transduction and transmission. Diverse collections of ion channels function in concert to transmit innocuous and noxious cold information. Under normal physiological conditions, the transduction of cold signals is aided by the activation of TRP channels such as TRPM8, TRPA1, and TRPC5, which likely engage in functional crosstalk during cold pain. GluK2 may represent a new cold transduction channel specifically tuned to detect noxious cold temperatures (i.e., below 10°C). Grueneberg ganglion (GG) neurons of the olfactory system lack TRPM8 and thus utilize alternative transduction mechanisms. Cold-sensing GG neurons require cGMP signaling to activate the cyclic nucleotide-gated (CNG) channel CNGA3 and the Guanylyl cyclase enzyme GC-G. Cold transmission, on the other hand, requires the activation of various voltage-gated sodium and potassium channels whose modulation is responsible for the perception of cold stimuli either through engaging excitability breaks, as seen with TREK channels TREK-1 and TREK-2 or by promoting repetitive firing like HCN channels and the Na_V1.1 voltage-gated sodium channel.