Functional significance of the platelet alpha2-adrenoceptor: studies in patients with myeloproliferative disorders.
Platelet alpha-adrenoceptor status was examined in 35 patients with myeloproliferative disorders (MPD) and 35 normal controls by means of radioligand binding studies with 3H-yohimbine (3H-YOH) and in vitro platelet function tests. A group of 'adrenaline insensitive' MPD patients identified in the functional studies were found to be identical to normal controls and other MPD patients with respect to their alpha 2-adrenoceptor status as assessed by the binding studies. Possible explanations for the dissociation between radioligand binding studies and functional responses in the platelet are discussed.
D000227:Adenine Nucleotides / Q000378:metabolism; D000293:Adolescent; D000328:Adult; D000368:Aged; D001792:Blood Platelets / Q000032:analysis*; D004837:Epinephrine / Q000494:pharmacology; D006801:Humans; D008875:Middle Aged; D009196:Myeloproliferative Disorders / Q000097:blood*; D010974:Platelet Aggregation / Q000187:drug effects; D011942:Receptors, Adrenergic, alpha / Q000032:analysis* / Q000502:physiology; D013929:Thromboxane B2 / Q000096:biosynthesis; D015016:Yohimbine / Q000378:metabolism
D000227:Adenine Nucleotides; D011942:Receptors, Adrenergic, alpha; D015016:Yohimbine; D013929:Thromboxane B2; D004837:Epinephrine