Table 1.

The 15 K2P channels expressed in mammals

Channel name	Gene name	Common name	Expression in DRG neurons
K2P1	KCNK1	TWIK1	Large/medium fibres, IB4‐ C‐fibrese
K2P2	KCNK2	TREK1	TRPV1+, C and medium fibresa , e
K2P3	KCNK3	TASK1	TRPV1+ fibresa , e
K2P4	KCNK4	TRAAK	Highly expresseda , e
K2P5	KCNK5	TASK2	Highly expresseda
K2P6	KCNK6	TWIK2	Highly expresseda
K2P7	KCNK7	Kcnk8	N/A
K2P9	KCNK9	TASK3	TRPV1‐, IB4‐ C‐fibresa , e
K2P10	KCNK10	TREK2	IB4+ C‐fibresa , d
K2P12	KCNK12	THIK2	Small > medium, large fibresa , b , e
K2P13	KCNK13	THIK1	Highly expresseda , b
K2P15	KCNK15	TASK5	N/A
K2P16	KCNK16	TALK1	N/A
K2P17	KCNK17	TALK2	N/A
K2P18	KCNK18	TRESK	Highly expressed in C‐fibres of DRG and TRGa , c , e

Mammals express 15 distinct K2P channels. Channel names are designated by IUPHAR (K2PX); however, the gene names (KCNKX) and historic names based on biophysical or pharmacological properties remain in common use. Abbreviations: TWIK, tandem of P‐domains in a weak inward rectifying K+ channel; TREK, TWIK‐related K+ channel; TASK, two‐pore domain, acid‐sensitive K+ channel; TRAAK, two‐pore domain‐related arachidonic acid‐activated K+ channel; THIK, two‐pore domain halothane‐inhibited K+ channel; TALK, two‐pore domain alkaline‐activated K+ channel; and TRESK, TWIK‐related spinal cord potassium channel. N/A is not applicable. See Figure 2. K2P6, 7, 12 and 15 channels pass little or no current when expressed in experimental cells. For more information, see the IUPHAR Guide to Pharmacology: http://www.guidetopharmacology.org/GRAC/FamilyDisplayForward?familyId=79. The expression pattern of K2P channels in DRG and TRG is summarized from the following:

^a Marsh et al. (2012);

^b Haskins et al. (2017);

^c Lafrenière and Rouleau (2011);

^d Acosta et al. (2014);

^e Pollema‐Mays et al. (2013).