Fig. 4.
Effect of extracellular Ca2+ on TRPA1-mediated whole cell currents in DRG neurons from TRPV1 knockout mice. A and B: AITC (50 μM)-induced whole cell currents exhibited an initial increase followed by a decrease. C and D: saturating concentration of AITC (1 mM)-induced currents exhibited profound tachyphylaxis.