The activation of TRPA1, but not TRPM8, induced Yo-Pro uptake. A, in HEK-293F cells expressing rat TRPA1, AITC elevated intracellular Ca2+, as represented by increases of fluorescence signals (RFU) in the FLIPR based Ca2+ assay. B, in cells expressing TRPA1, AITC evoked robust Yo-Pro uptake in a concentration-dependent manner from the FLIPR based Yo-Pro uptake assays. C, in cells expressing human TRPM8, menthol activated TRPM8 and elevated intracellular Ca2+. D, in cells expressing TRPM8, menthol failed to induce Yo-Pro uptake. Compounds are in μM and additions are indicated by arrows.