GLOSSARY 5-HT 3 R 5 5-HT 3 receptor; 12-HPETE 5 12-hydroperoxyeicosatetraenoic acid; ASIC 5 acid-sensing ion channel; ATP 5 adenosine triphosphate; BDNF 5 brain-derived neurotrophic factor; CGRP 5 calcitonin gene-related peptide; DRG 5 dorsal root ganglion; GDNF 5 glial-derived neurotrophic factor; HCN 5 hyperpolarization-activated cyclic nucleotide-gated; HTM 5 high threshold mechanical; IE 5 inherited erythromelalgia; K ATP 5 adenosine triphosphate-gated K 1 channel; Mrg 5 mas-related G-coupled protein receptor; Na v 5 voltage-gated sodium (Na 1 ) channel; NGF 5 nerve growth factor; PEPD 5 paroxysmal extreme pain disorder; PIP 2 5 phosphatidylinositol 4,5 biphosphate; PLC 5 phospholipase C; SFN 5 small fiber neuropathy; Slack 5 sequence like a Ca 21 -activated K 1 channel; TASK1 5 2-pore, acid-sensitive K 1 channel; TLR 5 Toll-like receptor; TMEM16 5 transmembrane protein 16; TRAAK 5 2-pore weak inwardly rectifying K 1 channel-related arachidonic acid-stimulated K 1 channel; TREK1 5 2-pore weak inwardly rectifying K 1 channel-related potassium channel-1; TRESK 5 2-pore weak inwardly rectifying K 1 channel-related spinal cord K 1 channel; TRP 5 transient receptor potential; TRPA1 5 transient receptor potential ankyrin 1; TRPM8 5 transient receptor potential melastatin 8; TRPV1 5 transient receptor potential vanilloid 1; TWIK1 5 2-pore weak inwardly rectifying K 1 channel.From the Department of Neurology, Mayo Clinic, Rochester, MN.Go to Neurology.org for full disclosures. Funding information and disclosures deemed relevant by the author, if any, are provided at the end of the article.