Figure 3

Digital fluorescence images of Nav1.7 immunolabeling (IL) of arterioles (Ar), arteriole-venule shunts (AVS) and associated innervation in normal human glabrous skin biopsies from the plantar foot (A,C,D) and palmar hand (B). All sections are labeled with an Alomone (A,C) or Yale (B,D) rabbit anti-rat Nav1.7 antibody revealed by a donkey anti-rabbit Cy3-conjugated secondary antibody (red fluorescence). Secondary antibodies conjugated to Alexa 488 (green fluorescence) were used to assess co-labeling for peptidergic sensory innervation revealed with a sheep anti-human CGRP antibody (A,B) or noradrenergic sympathetic innervation revealed with a sheep anti-human NPY antibody (C,D). Cell nuclei are labeled with DAPI (blue fluorescence). The left images in each panel show only the red fluorescence, the middle images only the green, and the right images the triple label combinations. Areas outlined in large white rectangles are 2X enlargement of the areas in the small rectangles. A-D. Nav1.7-IL is expressed on the endothelial cells of the tunica intima (red arrowheads) and on smooth muscle cells of the tunica media (tm). A,B. Peptidergic sensory innervation co-expresses Nav1.7-IL and CGRP-IL (yellow straight arrows). Other innervation labeled only with Nav1.7 (red curved arrows) is likely the noradrenergic sympathetic innervation that expresses NPY-IL as shown in C and D. C,D. Noradrenergic sympathetic innervation co-expresses Nav1.7-IL and NPY-IL (yellow curved arrows). Other innervation labeled with only Nav1.7 (red straight arrows) is likely the peptidergic sensory innervation that expresses CGRP-IL as shown in A and B. Scale Bar = 150 μm in A and B, 100 μm in C and D.