[Function of the serotoninergic system of blood platelets in patients with hypertension].

To investigate if there can be alterations in the 5-hydroxytryptamine (5-HT) uptake system in the sensitivity of platelets in patients with essential hypertension, 38 hypertensive patients and 37 normotensive healthy subjects were compared. In patients, the maximal 5-HT uptake velocity was reduced. The density of binding sites for 3H-imipramine was elevated in hypertensive females, but unchanged in males. The sensitivity of 5-HT uptake to trazodone was unchanged in patients. Half-maximal concentrations of 5-HT for inducing a shape change reaction of platelets were positively correlated with diastolic blood pressure in male patients and were reduced in female mild hypertensives. It is suggested that these changes are likely to be involved in the pathogenesis of hypertension.