Observations on the structural and innervation of the rat snout

Light and electron miscroscopy were employed to study the structure and innervation of the rat snout. The hairless skin at the tip of the snout was covered in epidermal ridges similar to the ridges seen on primate finger skin. Three types of nerve ending were observed in relation to the surface of snout: corpuscular, found in dermal papillae between epidermal rete ridges: hederiform, found in relation to Merkel cells at the base of the rete ridges; and free, which entered the epidermis from the sides and top of the dermal papillae. The evidence suggests that there may be two ultrastructurally distinct intraepidermal nerve fibres.