AP-18

AP-18 is a novel TRPA1 channel blocker (CHO cells, IC₅₀= 3.1µM; human and mouse cell lines, IC₅₀= 4.5µM). It reduces cinnamaldehyde-induced nociception in vivo and blocks cold- and mustard oil-induced activation of mouse TRPA1 but not capsaicin-induced activation demonstrating selectivity vs TRPV1. AP-18 was unable to block activation of TRPV1, TRPV2, TRPV3, TRPV4 or TRPM8 at concentrations up to 50μM. It reverses CFA-induced mechanical hyperalgesia in mice.