Figure 6

Menthol-evoked cold hypersensitivity is absent in Trpa1^-/- mice but present in Trpm8^-/- mice. A. Intraplantar administration of 25 mg menthol evoked marked cold hypersensitivity in the ipsilateral paw of lightly restrained Trpm8^-/- mice. Note that a greater cold hypersensitivity was seen in Trpm8^-/- than in wild-type mice. B. Menthol evoked cold hypersensitivity in wild-type but not Trpa1^-/- mice. Data show mean ± SEM for 6 mice/group. * p < 0.05, ** p < 0.01, *** p < 0.001 vs relevant predose values. † p < 0.05, †† p < 0.01, ††† p < 0.001 for contralateral-ipsilateral difference in wild-type mice.