Alopecia areata and affected skin CRH receptor upregulation induced by acute emotional stress

Background. Recent evidence indicates that acute stress can precipitate a n umber of dermatological conditions, including alopecia areata. This effect may be mediated by corticotropin-releasing hormone (CRH) released locally i n the skin from dorsal root ganglia or immune cells. CRH typically acts thr ough activation of specific receptors that are either type 1 or types 2 alp ha and 2 beta. CRH, or related peptides such as urocortin, could have proin flammatory effects directly or through activation of mast cells leading to destruction of the hair root. Objectives: To investigate the expression of CRH receptors on the affected skin of patients who developed alopecia areat a following acute emotional stress. Methods: Scalp skin biopsies were obtai ned from 1 normal volunteer and 3 patients after ring infiltration of the r elevant site with lidocaine. The biopsies were frozen and were later proces sed for in situ hybridization for CRH receptors type 1 or types 2 alpha and 2 beta. Sections showing positive results were photographed. Results: The skin from the normal volunteer showed weak background expression of all thr ee receptor types. However, skin from the affected sites of all 3 patients studied showed intense expression only on the type 2 beta receptor around t he hair follicles. Conclusion: Acute emotional stress may precipitate alope cia areata by activation of overexpressed type 2 beta CRH receptors around the hair follicles leading to intense local inflammation. Copyright (C) 200 1 S. Karger AG, Basel.