[Cyclic AMP accumulation in psoriatic skin: differential responses to epinephrine, AMP and histamine (author's transl)].

Epidermal adenylate cyclase can be activated independently by epinephrine, adenosine and histamine resulting in the accumulation of cyclic AMP. Using the uninvolved and involved keratome-sliced skin from psoriatic patients, we investigated the effects of these agents in vitro on the intra-cellular cyclic AMP levels of the skin. In the involved skin of psoriasis, epinephrine-induced cyclic AMP accumulation was decreased, whereas no decrease in adenosine- or histamine-induced cyclic AMP accumulation was seen. Since keratome-sliced skin samples had various amounts of dermal contamination, we also investigated the effect of epinephrine on the "pure" epidermal cyclic AMP level. After the incubation with epinephrine, pure epidermal samples, which were micro-dissected free from stratum corneum, dermis and skin appendages, were assayed for cyclic AMP level. Again cyclic AMP accumulation was decreased in the involved skin. Thus epinephrine-induced cyclic AMP accumulation was shown to be decreased in the involved epidermis of psoriasis.