Cyclosporin A induced augmentation of the beta-adrenergic adenylate cyclase response of pig epidermis

Abstract

It has been known that beta-adrenergic adenylate cyclase response is decreased in psoriatic-involved epidermis. Since the immunosuppressive agent, cyclosporin A, is reported to be effective on psoriasis clinically, the effect of cyclosporin A on beta-adrenergic adenylate cyclase response in pig skin was examined in vitro. Therapeutic serum levels of cyclosporin A (100–400 ng/ml) augmented the beta-adrenergic adenylate cyclase response of the epidermis. Highest levels of cyclosporin A (2–20 μg/ml) did not have any effect on its response. Both low K_m and high K_m cyclic AMP phosphodiesterases were not affected by cyclosporin A. Therefore, it is suggested that the clinical efficacy of cyclosporin A on psoriasis can be explained partially by its direct effect on the keratinocyte itself.