Fig. 5

NPY was not expressed by CGRP-IR sensory neurons after CCI. The presence of NPY (in green) in CGRP-positive primary afferents (in red) was assessed after CCI in the trigeminal ganglia (TG), the mental nerve (MN) and in the upper dermis of the skin. Representative images were taken from a CCI animal 6 weeks after surgery, but the same pattern was observed at 2 weeks (data not shown). NPY immunoreactivity was expressed by some cell bodies in the TG as well as by fibers, but these never co-expressed CGRP (a). NPY-IR fibers were seen in the mental nerve both proximal (inset) and distal to the CCI, but these fibers never co-expressed CGRP (b). In the skin, NPY-IR fibers never colocalized with CGRP, but were sometimes seen in close proximity (c). Dashed lines represent the border between the epidermis and the upper dermis. Scale bar = 50 μm TG: trigeminal ganglia, MN: mental nerve