title: In vitro histamine and serotonin release studies in atopic dermatitis.
abstract: 6 patients suffering from severe atopic dermatitis with high serum IgE were investigated. 3 of the patients had elevated plasma histamine levels (1.5-2.0 ng/ml). Compared to 9 nonatopic normal volunteers, the patient showed increased in vitro histamine release from peripheral leukocytes after stimulation with iothalamate and methacholine: while there was no significant histamine release at a methacholine concentration of 10(-4) M in normals, 4 of the patients with atopic dermatitis showed measurable histamine release under these conditions in vitro. The uptake of radiolabeled serotonin by platelets in vitro was decreased in 2 of the patients. There was no significant difference in serotonin release induced in vitro by different concentrations of thrombin, epinephrine and methacholine; 2 patients showed an increased platelet release reaction after iodipamide stimulation. It is concluded that a general tendency to release vasoactive mediators, even after 'nonimmunologic' stimulation, might play a role in the pathogenesis of atopic dermatitis.
mesh_terms: D000328:Adult; D003876:Dermatitis, Atopic / Q000276:immunology*; D005260:Female; D006632:Histamine / Q000097:blood; D006636:Histamine Release; D006801:Humans; D007073:Immunoglobulin E; D007483:Iothalamic Acid / Q000494:pharmacology; D007962:Leukocytes / Q000276:immunology; D008297:Male; D008875:Middle Aged; D012701:Serotonin / Q000378:metabolism*
chemical_list: D007483:Iothalamic Acid; D012701:Serotonin; D007073:Immunoglobulin E; D006632:Histamine