Kjeldsen S E, Gjesdal K, Leren P, Eide I K
Department of Internal Medicine, Oslo University Medical School, Ullevaal Hospital, Norway.
Thromb Haemost. 1988 Oct 31;60(2):251-4.
The content of free-catecholamines in blood platelets is much higher than in plasma and platelet catecholamines must be taken up from plasma, since platelets lack the enzymes for catecholamine synthesis. There is some evidence that platelet catecholamine content under certain circumstances may be an integrated measure of plasma catecholamine concentrations over time. Platelet-free catecholamines were therefore assayed in 18 untreated patients with essential hypertension and in 16 normotensive control subjects. Mean platelet-free dopamine in the hypertensive group was 3.7 +/- 0.4 pg/mg platelet weight, i.e. significantly less than the 6.5 +/- 0.9 pg/mg found in the normotensive (p less than 0.005). Platelet contents of noradrenaline and adrenaline did not differ. Decreased platelet-free dopamine and unchanged platelet noradrenaline and adrenaline persisted after adjustment for increased body weight in the hypertensive group. Although the reasons for decreased platelet-free dopamine in the hypertensive group remain unknown, this finding may add to previous result showing facilitated release of granular contents from blood platelets in patients with essential hypertension. Our data do not support platelet levels of free-catecholamines to be a marker of increased sympathetic tone in essential hypertension.
血小板中游离儿茶酚胺的含量远高于血浆，且血小板儿茶酚胺必须从血浆中摄取，因为血小板缺乏儿茶酚胺合成所需的酶。有证据表明，在某些情况下，血小板儿茶酚胺含量可能是血浆儿茶酚胺浓度随时间变化的综合指标。因此，对18例未经治疗的原发性高血压患者和16例血压正常的对照者进行了血小板游离儿茶酚胺的检测。高血压组血小板游离多巴胺的平均值为3.7±0.4 pg/mg血小板重量，明显低于血压正常组的6.5±0.9 pg/mg（p<0.005）。去甲肾上腺素和肾上腺素的血小板含量无差异。高血压组在对体重增加进行校正后，血小板游离多巴胺降低以及血小板去甲肾上腺素和肾上腺素不变的情况依然存在。虽然高血压组血小板游离多巴胺降低的原因尚不清楚，但这一发现可能补充了先前的结果，即原发性高血压患者血小板颗粒内容物的释放增加。我们的数据不支持血小板游离儿茶酚胺水平作为原发性高血压患者交感神经张力增加的标志物。
