Prostaglandins and cyclic AMP in epidermis

Prostaglandins E1 and E2 stimulate cyclic AMP accumulation in pig epidermis and in human epidermis from patients with psoriasis. Prostaglandins A1,A2 and F2alpha are relatively ineffective. The fact that this stimulation is not inhibited by a beta-blocker (propranolol) and that the stimulation by prostaglandin E2 and adrenaline is additive indicates that each drug acts independently on the epidermal adenyl cyclase system. In other words, prostaglandins E1 and E2 act on a site other than the beta-receptor of adenyl cyclase in epidermis. The stimulation by prostaglandins E1 and E2 is not additive; hence they probably act on the same site. Concentrations of prostaglandin E above 3X10(-7) M are effective in causing stimulation. This concentration may be within the physilogical range and the contribution of endogenous prostaglandin levels in the control of intracellular cyclic AMP levels cannot be disregarded.