Figure Legends.
Figure 1. Immunohistochemical demonstration of localization of CGRP, CT, Amylin and Adrenomedullin in the trigeminal ganglion.A. CGRP is expressed in a granular pattern in many neurons, mainly in small- to medium-sized neurons (arrow heads). The cellular CGRP is expressed in vesicles (insert). In addition, pearl-like CGRP immunoreactivity was detected in fibers that are of the C-type of sensory unmyelinated nerves (long arrows). The myelinated fibers do not contain CGRP. Short arrow points at a large negative neuron. B . CT immunoreactivity displayed a similar pattern as for CGRP; granular staining of small- to medium-sized neurons (arrow heads, insert) and pearl-like staining of fibers. Also, SGCs were CT immunoreactive (asterisks). Arrows point at a large negative neuron. C . AMY was exclusively expressed in the neurons, mainly small to medium sized (arrow heads). In some of the cells, the expression was granular, but in others, a general cytoplasmic immunoreactivity. Arrows point at a large negative neuron. Insert shows three different cells: one negative and two amylin immunoreactive. D . AM was expressed in the glial cells, both the SGCs (arrow heads) and cells enveloping the neuronal processes (arrows), probably myelinating cells.
Figure 2. Schematic illustration of the differential distribution of the CGRP family of peptides and receptors. The CGRP receptor (CLR/RAMP1) is mainly expressed in the large neurons and SGCs, the Adrenomedullin2 receptor (CLR/RAMP3) in some SGCs, the Amylin1 receptor (CTR/RAMP1) in large neurons and SGCs, and the Amylin3 receptor (CTR/RAMP3) in some SGCs Modified from Edvinsson, Grell & Warfvinge, 2020.