Fig. 3
From: Peripheral signaling pathways contributing to non-histaminergic itch in humans
Application modes affect the area of axon-reflex erythema. A Laser-speckle imaging after microinjection (left panel) or focal application (right panel) of pruritogens. The intensity of the signal is color coded from light blue to red (color palette at the bottom). B Area of axon-reflex erythema after microinjection of the pruritogens (upper panel) and after focal application (bottom panel). A widespread axon-reflex erythema occurs once it reaches a threshold area of 1 cm2 (gray dashed line)