Fig. 4

Attenuation of the pruritogen-induced activation of PAG neurons in orexin-neuron-ablated mice. A c-Fos expression (green) in lPAG/vlPAG neurons (red) after intradermal injection of vehicle or chloroquine into WT and ORX-abl mice. B The densities of c-Fos-positive neurons in the lPAG/vlPAG area after intradermal administration of vehicle or chloroquine were plotted. The c-Fos expression level after chloroquine injection was significantly decreased in ORX-abl mice compared with that in WT mice. The data represent the mean ± SEM. **P < 0.01, ***P < 0.001 (two-way ANOVA with post hoc Tukey’s multiple comparison test), n = 5 for all groups