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

BACKGROUND

Recent evidence indicates that acute stress can precipitate a number of dermatological conditions, including alopecia areata. This effect may be mediated by corticotropin-releasing hormone (CRH) released locally in the skin from dorsal root ganglia or immune cells. CRH typically acts through activation of specific receptors that are either type 1 or types 2 alpha and 2 beta. CRH, or related peptides such as urocortin, could have proinflammatory 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 areata following acute emotional stress.

METHODS

Scalp skin biopsies were obtained from 1 normal volunteer and 3 patients after ring infiltration of the relevant site with lidocaine. The biopsies were frozen and were later processed 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 three receptor types. However, skin from the affected sites of all 3 patients studied showed intense expression only on the type 2 beta receptor around the hair follicles.

CONCLUSION

Acute emotional stress may precipitate alopecia areata by activation of overexpressed type 2 beta CRH receptors around the hair follicles leading to intense local inflammation.