title: Platelet secretion defect in patients with the attention deficit disorder and easy bruising.
abstract: Platelet function was evaluated in 12 patients with the attention deficit disorder and lifelong history of easy bruising. Aggregation and 14C-serotonin secretion studies in platelet-rich plasma in response to adenosine diphosphate (ADP), epinephrine, and arachidonic acid did not reveal striking abnormalities. Secretion of adenosine triphosphate (ATP), ADP, beta-hexosaminidase, and beta-glucuronidase by gel-filtered platelets in response to the divalent cation ionophore A23187 and low concentrations of thrombin (less than or equal to 0.1 U/ml) was impaired in patients as compared to normals. The aggregation response to A23187 (4 microM) was absent in 8 of the 12 patients. The total stores of the secretable constituents, the retention of incorporated 14C-serotonin, and the arachidonate metabolism of the platelets were normal. Our findings suggest a new platelet disorder with impaired secretion mechanism, without storage pool deficiency or impaired arachidonate metabolism. The secretion defect in platelets represents a tissue disorder in a functional psychiatric disease. We refocus attention on the role of platelets as a model for neurons in functional disorders, with emphasis on secretion mechanisms rather than amine uptake, storage, and metabolism.
mesh_terms: D000293:Adolescent; D000328:Adult; D001095:Arachidonic Acids / Q000378:metabolism; D001289:Attention Deficit Disorder with Hyperactivity / Q000097:blood* / Q000150:complications; D001791:Blood Platelet Disorders / Q000150:complications*; D001792:Blood Platelets / Q000378:metabolism*; D002648:Child; D002850:Chromatography, Gel; D005260:Female; D006487:Hemostasis; D006801:Humans; D008297:Male; D010974:Platelet Aggregation; D012701:Serotonin / Q000378:metabolism; D013929:Thromboxane B2 / Q000096:biosynthesis
chemical_list: D001095:Arachidonic Acids; D012701:Serotonin; D013929:Thromboxane B2