Immunofluorescent photomicrographs showing expression of transient receptor potential vanilloid subfamily type 1 (TRPV1) and P2X3 in the L5 dorsal root ganglion from an animal injected with fast blue (FB) into gastrocnemius muscle. The arrowheads indicate the FB-positive cells do not expressing TRPV1. The arrows indicate the FB-positive cells also expressing TRPV1, but not P2X3.