Greger J L, Tseng E
Department of Nutritional Sciences, University of Wisconsin, Madison 53706.
Proc Soc Exp Biol Med. 1993 Jul;203(3):377-85. doi: 10.3181/00379727-203-43615.
The effects of supplemental NaCl, KCl, and Na acetate on the blood pressure of weanling rats fed semipurified diets and diets based on naturally high salt products, like cottage cheese, were examined in two studies. Within 2 weeks of initiation of dietary treatments, rats fed supplemental chloride had elevated blood pressure and lowered plasma renin activity, which persisted throughout the 8-week study. The effect of supplemental sodium on blood pressure was not significant until after 6 weeks of dietary treatment. The initial increase in blood pressure preceded the slowed growth observed in rats fed excess chloride or sodium. Urinary volume and urinary excretion of calcium, magnesium, phosphorus, sodium, and chloride were increased when supplemental chloride or sodium was fed, but tissue electrolyte and plasma atrial natriuretic peptide concentrations remained constant. Two changes preceded the rise in blood pressure: rats fed supplemental chloride had enlarged kidneys, and those fed supplemental sodium had elevated hematocrits, suggesting a transient shift among fluid compartments, after only 6 days of treatment. These data suggest that the hypertension induced by ingestion of supplemental (14.6 mg CI/g of diet) chloride is mediated by changes in renal function. Ingestion of excess sodium depressed bone magnesium concentrations in Study 1 and after 24 days in Study 2; the impact of this "relative" magnesium depletion on blood pressure deserves further study.
在两项研究中，研究了补充氯化钠、氯化钾和醋酸钠对食用半纯化日粮以及以天然高盐产品（如白软干酪）为基础的日粮的断奶大鼠血压的影响。在开始饮食处理的2周内，喂食补充氯化物的大鼠血压升高，血浆肾素活性降低，这种情况在整个8周的研究中持续存在。直到饮食处理6周后，补充钠对血压的影响才显著。血压的最初升高先于喂食过量氯化物或钠的大鼠出现生长减缓。当喂食补充氯化物或钠时，尿量以及钙、镁、磷、钠和氯的尿排泄量增加，但组织电解质和血浆心钠素浓度保持不变。血压升高之前有两个变化：喂食补充氯化物的大鼠肾脏增大，喂食补充钠的大鼠血细胞比容升高，这表明仅在处理6天后，体液隔室之间发生了短暂的变化。这些数据表明，摄入补充（14.6毫克氯/克日粮）氯化物所诱发的高血压是由肾功能变化介导的。在研究1中以及研究2的24天后，摄入过量钠会降低骨镁浓度；这种“相对”镁缺乏对血压的影响值得进一步研究。
