Coruzzi P, Musiari L, Mossini G L, Ceriati R, Novarini A
Institute of Semeiotica Medica, University of Parma, Italy.
Scand J Clin Lab Invest. 1993 Oct;53(6):593-9.
It has been demonstrated that an exaggerated natriuretic response to central hypervolaemia is not necessarily associated with hypertension; many hypertensive subjects manifest either an appropriate or a blunted natriuresis in response to ECFV expansion attained by head-out water immersion. In this study, we tested the hypothesis that an underlying condition of salt-sensitivity may explain the heterogeneity of the natriuretic response of essential hypertension. Both salt-sensitivity tests and 2h water-immersion studies were randomly performed in 18 untreated essential hypertensives under a selected and controlled diet. Salt-sensitivity was defined as a significant drop in mean arterial pressure of 10% or greater, calculated as the difference between the average of the 25 readings under the high and the low salt period. Water immersion did result in a significant natriuretic and calciuretic response in the whole hypertensive group (n = 18, p < 0.001 and p < 0.05, respectively), while the examination of the individual excretion disclosed either exaggerated and appropriate or blunted urinary response. When the hypertensive group was classified in relation to salt-sensitivity, the greater fall in mean arterial pressure during low salt diet (salt-sensitivity) was associated with the more pronounced natriuretic response during water immersion (r = -0.66, p < 0.003). An identical correlation (r = -0.58, p < 0.01) was also found between changes in mean arterial pressure (low salt diet) and urinary calcium excretion (water immersion) in the same hypertensives. The water immersion-induced suppression of plasma aldosterone and the increase in plasma atrial natriuretic peptide did result from comparable magnitude in the salt-sensitive and in salt-resistant subjects.(ABSTRACT TRUNCATED AT 250 WORDS)
业已证明，对中枢性血容量过多的利钠反应过度并不一定与高血压相关；许多高血压患者在通过头低位浸水使细胞外液量（ECFV）增加时，表现出正常或减弱的利钠反应。在本研究中，我们检验了盐敏感性这一潜在状况可能解释原发性高血压利钠反应异质性的假说。在选定的控制饮食条件下，对18例未经治疗的原发性高血压患者随机进行盐敏感性试验和2小时浸水研究。盐敏感性定义为平均动脉压显著下降10%或更多，计算方法为高盐期和低盐期25次读数平均值之间的差值。浸水确实在整个高血压组（n = 18，分别为p < 0.001和p < 0.05）中导致了显著的利钠和利钙反应，而对个体排泄情况的检查发现，尿反应要么过度且正常，要么减弱。当根据盐敏感性对高血压组进行分类时，低盐饮食期间平均动脉压下降幅度更大（盐敏感性）与浸水期间更明显的利钠反应相关（r = -0.66，p < 0.003）。在同一组高血压患者中，低盐饮食期间平均动脉压变化与尿钙排泄（浸水时）之间也发现了相同的相关性（r = -0.58，p < 0.01）。盐敏感和盐抵抗受试者中，浸水诱导的血浆醛固酮抑制和血浆心钠素增加幅度相当。（摘要截短于250字）
