The pore properties of human nociceptor channel TRPA1 evaluated in single channel recordings

► Human TRPA1 channel weakly discriminates among both mono- and divalent cations. ► PX+/PNa+s are Li+ (1.26) ≥ K+ (0.98) ≥ Rb+ (0.98) > Cs+ (0.95). ► PY2+/PNa+s are Ca2+ (5.1) > Ba2+ (3.5) > Mg2+ (2.8). ► Some ligands recruit the hTRPA1 channel to a state permeable to large organic cations. ► The pore of the channel in this state is dilated by approximately 1-2.5 Å