Age-dependent decrease of α2-adrenergic receptor number in human platelets

Reduced thrombus stability in mice lacking the α2A-adrenergic receptor

“…It is known that the density of ␣ 2A on the platelet surface can vary in relation to physiologic, pathologic, and pharmacologic factors. Furthermore, it has been reported that age, 32 ischemic heart failure, 33 and plasmatic catecholamine levels 34,35 can regulate ␣ 2A expression. In line with this, Wang and Cheng 36 have found that strenuous exercise increases platelet ␣ 2A -adrenergic receptor density and can enhance platelet adhesiveness on fibrinogen-coated surfaces.…”

Platelet Alpha₂-Adrenergic Receptor Binding and the Effects of <i>d</i>-Amphetamine in Boys with Attention Deficit Hyperactivity Disorder

“…All the chil dren were placed on VMA exclusion low monoamine diet. Some foods, particularly certain fruits and vegetables, contain catechol amines and phenol derivatives [22][23][24], It is also known that the number of alphaj-adrencrgic receptors on the platelets is regulated by circulating catecholamines [25,26]. Therefore, we thought that giv ing low monoamine vanyl-mandelic acid exclusion diet would mini mize the effects of exogenous catecholamines on platelet alphajadrcncrgic receptor numbers.…”

The effect of ageing on human platelet sensitivity to serotonin

“…As expected, adrenaline increased in the plasma of elderly people [9], an effect that would be expected to increase the plasma level of cAMP by stimulating P-adrenoceptors in the whole vascular bed [ 151. However, no such increase in plasma cAMP was observed in this study, a result that is compatible with the proposed general 'down-regulation' of the functional capacity of P-adrenoceptors in elderly people 171.…”