Alteration of platelet alpha 2-adrenoceptors in human hypertension.
We have previously demonstrated an alteration in cerebral and renal alpha 2-adrenoceptor densities in hypertensive rats. Since human platelets contain alpha 2-adrenoceptors, these receptors were measured in normotensive and hypertensive subjects using [3H]-rauwolscine to determine whether there was an alteration of alpha 2-adrenoceptors in human hypertension. In normotensive subjects, [3H]-rauwolscine bound to distinct high- and low-affinity alpha 2-adrenoceptor sites. In contrast, in platelets of hypertensive patients only the high-affinity alpha 2-adrenoceptor site was detectable. In addition, platelet alpha 2-adrenoceptor densities were higher in normotensive than in hypertensive subjects. This alteration, if present in other cells, could be important in the pathogenesis of hypertension.
D000328:Adult; D000368:Aged; D001792:Blood Platelets / Q000032:analysis* / Q000378:metabolism; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood*; D008297:Male; D008875:Middle Aged; D011869:Radioligand Assay; D011942:Receptors, Adrenergic, alpha / Q000032:analysis* / Q000378:metabolism; D014316:Tritium; D015016:Yohimbine / Q000097:blood
D011942:Receptors, Adrenergic, alpha; D014316:Tritium; D015016:Yohimbine