Pathogenesis of hypertension and interraction of vasoactive hormones

高血压病患者给予高钠饮食和血压，观察到各种血管活性激素的相互作用。盐敏感患者去甲肾上腺素的抑制和PGE_2的升高不足。在盐平衡研究中，正常血压患者的PRA和PGE_2呈线性关系。补钾可降低高血压病患者的血压，钾的降压作用与钠负荷引起的血压升高幅度有关。高钾摄入时PGE_2升高至少部分参与了降压机制。口服钙负荷8周可降低老年高血压患者的血压。降压的机制是多因素的。降低PTH后血浆维生素D3的抑制被认为是机制之一，表明细胞内钙离子在高血压的维持中起着重要作用。用放射免疫法和Na~+抑制法同时测定循环中的前列腺素样因子高血压患者的K-ATPase抑制随着钠负荷的增加而增加。血浆哇巴因样抑制物水平与血压和尿钠排泄量均呈正相关。提示内源性哇巴因样钠泵抑制物在高钠摄入量高血压的病理生理过程中起重要作用。该因子的分离和鉴定目前正在进行中。该方法为R-A研究提供了一种新的工具。

Patients with essential hypertension were placed on high sodium diet and BP and various vasoactive hormonal interaction were observed.Suppression of norepinephrine and increase in PGE2 wereinsufficient in salt-sensitive patients.The relationship between PRA and PGE2 during salt balance study was linear in normotensive subjects,however the rellation was disturbed in hypertensive patients.Potassium supplement lowered BP in hypertensive patients with high sodium diet and hypotensive effects of potassium correlated with the magnitude of BP increase caused by sodium loading.Increased PGE2 during high K intake involved at leaset partially in the hypotensive mechanism.Oral calcium loading for 8 weeks lowered BP in elderly hypertensive patients.The mechanism of BP reduction is multifactorial.Suppression of plasma vit.D3 following reduction of PTH is suggested as one of the mechanism,indicating the inportance of intracellular Ca ion in the maintenance of hypertension.Circulating ouabain-like factor determined by both RIA and the method of inhibition of Na,K-ATPase inhibition was incresed by sodium loading in patients with essential hypertension.Plasma level of ouabain-like inhibitor correlated with both BP and urinary sodium excretion.Thus it is suggested that the endogenous ouabain-like sodium pump inhibitor plays an important role in the pathophysiology of high blood pressure induced by high sodium intake.Isolation and identification of this factor in now in progress.A sensitive human renin RIA has been developed for clinical use.The antibody recognize both active and inactive from of renin and renin level measured by this RIA express total renin. This method provides a new tool for the R-A study.