Sanchez Ramiro, Fischer Patricia, Cuniberti Luis, Masnatta Lucas D, Ramírez Agustín J
Hypertension and Metabolic Unit Section, ICYCC, Fundación Favaloro, Buenos Aires, Argentina.
J Hypertens. 2007 Dec;25(12):2434-40. doi: 10.1097/HJH.0b013e3282f03597.
Nonmodulating hypertension (NMHT) is a high-renin subtype of salt-sensitive hypertension due to renal hemodynamic alterations.
To evaluate, in NMHT, whether the increased oxidative stress, which interferes with endothelial function, could be the consequence of an elevated renin-angiotensin activity and insulin resistance.
Fourteen patients with NMHT and 12 with modulating hypertension (MHT) were included. Plasma renin activity (PRA) and glucose/insulin tolerance test were performed and homeostasis model assessment (HOMA) index and areas under the curves (AUC) calculated. Urinary nitrites and nitrates (NOx), urinary cyclic guanosine monophosphate (cGMP) activity, urinary isoprostanes and plasma nitrotyrosine levels were also measured.
PRA was higher in NMHT than MHT. In addition, L-arginine infusion increased effective renal plasma flow in MHT but not in NMHT. Insulin levels were higher in NMHT both at fasting and at 120 min, as were HOMA and AUC values. In MHT, NOx and cGMP significantly increased when moving from low to high Na+ intake, while nitrotyrosine mass and isoprostanes failed to show any change. On the contrary, in NMHT under low Na+ intake, urinary NOx levels were significantly higher than MHT under high Na+ intake, and failed to show any change under high Na intake; cGMP also failed to show any change when patients moved from low to high Na+ intake. Nitrotyrosine mass and isoprostanes, like to NOx, were significantly higher in NMHT under both low and high Na+ intake.
It is suggested that, in NMHT, a possible association between higher renin-angiotensin system activity, insulin resistance and endothelial dysfunction, showed for the first time in the same subjects, might result in systemic vascular and renal endothelial dysfunction, salt-sensitive hypertension and high cardiovascular risk.
非调节性高血压（NMHT）是一种因肾血流动力学改变导致的盐敏感性高血压的高肾素亚型。
在非调节性高血压中，评估干扰内皮功能的氧化应激增加是否可能是肾素 - 血管紧张素活性升高和胰岛素抵抗的结果。
纳入14例非调节性高血压患者和12例调节性高血压（MHT）患者。进行血浆肾素活性（PRA）和葡萄糖/胰岛素耐量试验，并计算稳态模型评估（HOMA）指数和曲线下面积（AUC）。还测量了尿亚硝酸盐和硝酸盐（NOx）、尿环磷酸鸟苷（cGMP）活性、尿异前列腺素和血浆硝基酪氨酸水平。
非调节性高血压患者的PRA高于调节性高血压患者。此外，L - 精氨酸输注增加了调节性高血压患者的有效肾血浆流量，但非调节性高血压患者未增加。非调节性高血压患者空腹和120分钟时的胰岛素水平、HOMA和AUC值均较高。在调节性高血压中，从低钠摄入到高钠摄入时，NOx和cGMP显著增加，而硝基酪氨酸质量和异前列腺素未显示任何变化。相反，在低钠摄入的非调节性高血压中，尿NOx水平显著高于高钠摄入的调节性高血压，高钠摄入时未显示任何变化；当患者从低钠摄入转变为高钠摄入时，cGMP也未显示任何变化。在低钠和高钠摄入情况下，非调节性高血压患者的硝基酪氨酸质量和异前列腺素与NOx一样显著更高。
提示在非调节性高血压中，首次在同一受试者中显示的较高肾素 - 血管紧张素系统活性、胰岛素抵抗和内皮功能障碍之间的可能关联，可能导致全身血管和肾内皮功能障碍、盐敏感性高血压和高心血管风险。
