In vitro cyclic nucleotide responsiveness of leukocytes and platelets in patients suffering from atopic dermatitis.

Peripheral blood leukocytes from patients with severe atopic dermatitis (serum IgE levels between 1,560 and 28,000 U/ml) showed a significantly weaker increase in intracellular cAMP after stimulation with epinephrine (10(-5)-10(-3) M) than leukocytes from normals. At the same time stimulation with methylcholine (10(-10)-(10(-4) M) induced a significantly higher increase in intracellular levels of cGMP in the atopic group compared to normals. The immunomodulating agent levamisole induced a slight increase in cAMP and cGMP response both in leukocytes from atopic patients and in normals. Platelet cAMP concentrations were lowered by epinephrine stimulation both in atopics and controls. There was no effect of methylcholine upon platelet cyclic nucleotide levels in the dose range examined. The data support the concept that abnormal cyclic nucleotide responsiveness--not only as beta-adrenergic blockade but also as cholinergic hyperreactivity--may plays a role in the pathogenesis of atopic dermatitis.