Abstract
Background Serotonin implication in allergic contact dermatitis was earlier suggested.
Objective To study the expression of serotonin (5-HT) and its receptors 1A and 2A during the kinetics of allergic contact dermatitis (ACD).
Method Biopsies from 10 female nickel-allergic patients were obtained at 0, 6, 24, 48 and 72 h after nickel application using a patch testing procedure and then analysed by immunohistochemistry.
Results Higher 5-HT epidermal immunoreactivity was seen at 0 and 6 h compared with 24, 48 and 72 h. The number of 5-HT labelled platelets was higher at 48 and 72 h compared with 0, 6 and 24 h. There was a decrease in the number of 5-HT1AR positive cells at 24, 48 and 72 h compared with 0 h. Furthermore, epidermal 5-HT1AR immunoreactivity was stronger at 48 and 72 h compared with 0 h. Total (dermis plus epidermis) number of 5-HT2AR positive cells was gradually increased in a time-dependent manner at 6, 24, 48 and 72 h compared with 0 h.
Conclusions Our results suggest the implication of 5-HT, 5-HT1AR and 5-HT2AR in the development of human ACD and the possibility to target those receptors at an early stage of this inflammatory condition. Received: 5 August 2010; Accepted: 29 November 2010