The co-localization of TRPV1/A1 and GFRα3 was higher than that of TRPV1/A1 and TrkA. A-D: Colocalization of TRPV1 or TRPA1 mRNA (clusters of solver grains; triangle heads) and TrkA (A and B) or GFRα3 (C and D) mRNA (brown cells) using double ISHH with 35S-labeled antisense TRPV1 or TRPA1 probes combined with DIG-labeled TrkA or GFRα3 probe. The brightfield and darkfield photographs are merged. Arrows indicate examples of double-labeled neurons. Bars: 50 μm (A-D).