Glial cell line-derived neurotrophic factor family receptor α3 (GFRα3)-like immunoreactivity (-LI) and transient receptor potential ion channel 1 (TRPV1)-LI were seen in 17.7 ± 1.4% and 43.2 ±1.7%, respectively, of dural true blue back-labeled neurons in adult rat trigeminal ganglia (TG). All GFRα3-LI neurons were also TRPV1-LI. Example of dural afferent that was (A) positively labeled for both GFRα3 and TRPV1 (arrow), labeled for only TRPV1 (arrowhead), and (B) negatively labeled (arrows). (C) Controls in which the primary antibody was omitted show lack of reactivity. Scale bar, 100 μm.