The proposed allosteric model reproduces the experimental data of TRPV1 wild type and I696X mutants. The figure depicts the normalized g-V curves obtained for the I696X mutants in the absence (A) and presence of capsaicin at 1 µM (B) and 100 µM (C). Solid lines depict the best fit to the allosteric model. Normalized g-V curves in the absence of capsaicin were fitted to Eq. 1, and results are given in Table 3. Normalized g-V curves in the presence of capsaicin were fitted to Eq. 3, fixing the values for the equilibrium constants obtained in the absence of capsaicin: J_o = 0.021, L = 5.0 × 10⁻⁴, K_d = 10⁻⁵, and z_g = 0.6. The value of E given by the analysis was virtually 1 and, therefore, was kept constant to this value. The values obtained for allosteric constants P and D and free energy are depicted in Table 4.