In the phase plot analysis (Figures 2E,F), there was a significant increase in AP threshold (control: −35.6 mV, n = 16; calcipotriol: −29.3 mV, n = 22, p < 0.0001, unpaired Student’s t-test, Figure 2G) and a decrease (6.8%) in the maximum dV/dt when transitioning from the resting membrane potential to the peak of the AP (Figure 2H), with a larger AP half-width in the calcipotriol-treated group (control: 2.9 ms, n = 14, calcipotriol: 3.5 ms, n = 15, p < 0.05, unpaired Student’s t-test, Figure 2I), suggesting a decreased excitability of NPY+ neurons under chronic itch conditions. This evidence concerns the gene NPY and Pruritus.