Full sensitization is depicted in this slide. The C fiber and A-delta fiber depicted on the top are degenerated, while the C fiber and A-delta fiber on the bottom are intact. The normal, intact C fibers express alpha-adrenergic receptors, TRPV1 receptors, and sodium channels. The sodium channels on the A-delta fibers receive increased, spontaneous stimulation from these damaged fibers, which produces peripheral sensitization.