高血压病患者心脏指数、外周阻力及外周血液淋巴细胞β受体的检测

The determination of cardiac index,total peripheral resistance and peripheral lymphocyte adrenergic beta receptors in patients with essential hypertension

本实验应用放射配体结合法和超声心动图法分别测定了稳定型高血压病患者的外周血液淋巴细胞β受体密度和亲合力以及心脏指数和外周总阻力,并与正常人组进行了比较。结果显示高血压患者外周血液淋巴细胞β受体密度比正常人组值低(238±107对318±130 fmol/10~7细胞,P<0.05);二组之受体与配体复合物的平衡解离常数KD分别为2.62±1.25,3.31±1.14nm,二组间无显著差异(P>3.05)。高血压患者的心脏指数尚无显著性降低(3.92±1.06对4.54±1.09 L/min/M^2,P>0.05)而外周总阻力则明显增高(2811±711对1798±484 dynes sec.cm^(-3).M^2,P<0.01)。鉴于外周血液淋巴细胞β受体密度与心肌β受体密度呈正相关且受内源性儿茶酚胺的调节,本结果提示在稳定性高血压阶段也必然存在着心肌β受体密度的下降。我们认为这可能是高血压时尽管心脏所接受的肾上腺激素能刺激增加,但心排出量却不相应地增加甚至有下降趋势的原因之一。

In this study, beta-adrenoceptor density and affinity of peripheral lymphocytes from patients with established hypertension were measured by radioligand binding assay while cardiac index(CI)and total peripheral resistance(TPR)were determined by echocardiography in comparison with those of normotensive volunteers. The result showed as followings: maximum binding capacity (Bmax) of lymphocytes from hypertensive was lower than that from normotensives (238±107 vs 348±130 fmol/10~7 cells, P<0.05 ). KD of hypertensives and normotensive was 2.62±1.25, 2.31±1.14 nM respectively, no significant difference was found (P>0.05). Our result demonstrated that these was nosignifieant difference in CI between hypertensive and normotensive statistically (3.92±1.06 vs 4.54±1.09 L/min./M^2, P<0.05). However, elevation of TPR was found in hypertensives(2811±711 vs 1798±484 dynes sec.cm ^(-5)M^2 P<0.01). Since betaadrenoceptor density in peripheral lymphocytes is positively correlated with that of the corresponding cardiac muscle cells and which is regulated by endogenous catecholamines, our result suggested that in established hypertension, there may also de a decrease of myooaidial beta-reoeptor density. This might be the resson why CI fails to increase correspondingly with the incressed adrenergic,stimuli in hypitension.