Nerve outgrowth and neuropeptide expression during the remodeling of humanburn wound scars - A 7-month follow-up study of 22 patients

Increasing data suggest that the skin nerve system is involved in wound hea ling. The objective of this study was to investigate the outgrowth of nerve fibers during the burn wound remodeling process and to analyze possible di fferences between normotrophic and hypertrophic burn wounds. In a prospecti ve study, biopsies were taken from 22 patients with spontaneously healed pa rtial-thickness burns at 1, 4 and 7-month post-burn. Nerve outgrowth and th e expression of the neuropeptides substance P, neurokinin A, calcitonin gen e-related peptide, vasoactive intestinal peptide and neuropeptide Y was mon itored using immunohistochemistry. Our results showed that the number of ne rve fibers gradually increased in both the dermis and the epidermis, but th at they did not reach the levels of expression present in matched unburned skin of the same patient. A significantly higher number of nerve fibers wer e observed in normotrophic scars compared with hypertrophic scars. The numb er of neuropeptides-containing nerves in normotrophic and hypertrophic scar s were similar. In conclusion: 7 months after wound closure, burn wound sca rs contain less nerve fibers than unburned skin. The significantly higher n umber of nerve fibers in normotrophic, compared with hypertrophic scars sug gests a regulatory role for the skin nerve system in the outcome of burn wo und healing. (C) 2001 Elsevier Science Ltd and ISBI. All rights reserved.