Prostaglandin E2 induces vasodilation and pruritus, but no protein extravasation in atopic dermatitis and controls

Background: Prostaglandin E-2 (PGE(2)) has well-established vasodilatory effects, whereas its effects on protein extravasation and its sensory effects are less clear. Objective: Vasoactive effects of PGE(2) were correlated to its ability to evoke pain or itch in healthy volunteers and patients with atopic dermatitis (AD). Methods: Intradermal microdialysis was used to apply PGE(2) (10(-8)-10(-4) M) via microdialysis capillaries in 8 patients and 8 controls. Large pore size membranes (3000 kd) enabled simultaneous analysis of protein extravasation. Itch and pain sensations were measured psychophysically, and Superficial blood flow was measured by laser Doppler imaging. Results: PGE(2) close dependently provoked intense local vasodilation, weak pruritus, and pain, but no protein extravasation. No differences were found between patients with AD and controls for any, parameter. Conclusion: We conclude that PGE(2) is a potent vasodilator and a weak pruritic agent in normal skin and in patients with AD, but does not provoke increased protein extravasation.