Figure 3.

TRPV1 S801A KI mice show attenuated sensitization of capsaicin-evoked current response by PMA. A, Densities of currents evoked by 0.4 or 10 μm capsaicin in dissociated DRG neurons from WT and KI mice. The numbers within parentheses represent the number of neurons. NS, not significant (left, p = 0.61; right, p = 0.63 in Student's t test). B, Rising time (10–90%) of currents evoked by 10 μm capsaicin in dissociated DRG neurons from WT and KI mice. NS, not significant (p = 0.73 in Student's t test). C, D, Representative current traces evoked by capsaicin in dissociated DRG neurons from WT (C) or KI (D) mice. The currents were recorded by whole-cell voltage clamp at −60 mV and 0.4 or 10 μm capsaicin and 0.3 μm PMA was applied as indicated. Current amplitudes were normalized to the current amplitude evoked by 10 μm capsaicin in each neuron. E, Extent of PMA-mediated sensitization of responses evoked by first and second application of 0.4 μm capsaicin that were normalized to the response by 10 μm capsaicin in each neuron. ***p < 0.001; ****p < 0.0001 in Bonferroni's post hoc test after two-way repeated-measures ANOVA, #p < 0.05; ###p < 0.001; ####p < 0.0001 in Bonferroni's post hoc test between first and second currents. Numbers within parentheses represent the numbers of cells analyzed.