A preliminary report: the changes in the neuropeptide containing epidermal innervation in response to inflammatory reactions elicited in human breast skin.

A pilot study was performed to demonstrate the involvement of the epidermal innervation in cutaneous neurogenic inflammation following injury or skin incision. Scratching human skin is known to evoke an inflammatory reaction dependent in part on sensory nerves (neurogenic inflammation) in the dermis. Human breast skin from four patients was scratched using a blunt metal ruler to elicit an inflammatory reaction. Samples of skin along the scratch line were then removed before and up to 5 min after scratching. Tissue samples were then stained using immunocytochemical techniques for the neuropeptides PGP 9.5, SP, CGRP and VIP. Quantitative assessment using image analysis demonstrated a marked variation between patients in the levels of epidermal PGP 9.5 innervation prior to scratching of the skin. In addition both increases and decreases in the epidermal innervation of PGP 9.5 were observed in different patients immediately after scratching. It is considered that epidermal innervation may have an important role in the inflammatory reaction to trauma and surgical operations and that a more extensive study is merited.