ABSTRACT
<p><b>OBJECTIVE</b>Salt-sensitivity plays an important role in essential hypertension and is associated with more severe target organ injury and higher mortality in patients with essential hypertension. However, the pathologic mechanism of salt-sensitivity is poorly understood and endothelial dysfunction might be involved in salt-sensitive hypertension. We, therefore, observed the endothelial function changes by measuring plasma and urine nitric oxide (NO) concentrations in salt-sensitive (SS) normotensive and mild hypertensive subjects underwent various salt loading protocols and the effects of potassium supplement.</p><p><b>METHODS</b>Thirty-nine normotensive and mild hypertensive subjects (< 160/100 mm Hg), aged 16-60, were enrolled and the study protocol is as follows: 3 days baseline investigation, 1 week low-salt loading (3 g/day), 1 week. high-salt loading (18 g/day) and 1 week high-salt loading plus potassium chloride (4.5 g/day).</p><p><b>RESULTS</b>Plasma and urine NO levels were significantly lower in SS (n = 8) subjects at baseline, low-salt and high-salt loading phases compared with salt-resistant subjects (SR, n = 31) and oral potassium supplement to SS subjects with high salt loading significantly increased plasma and urine NO levels.</p><p><b>CONCLUSION</b>Endothelial function is impaired in normotensive and mild hypertensive SS subjects. Oral potassium supplement could improve endothelial function in normotensive and mild hypertensive SS subjects.</p>
Subject(s)
Adult , Female , Humans , Male , Antihypertensive Agents , Blood Pressure , Endothelium , Physiology , Hypertension , Epidemiology , Nitric Oxide , Blood , Urine , Potassium, DietaryABSTRACT
<p><b>OBJECTIVE</b>To investigate the effects of potassium and calcium supplementation in table salt on reduction of arterial blood pressure and sodium metabolism in adolescents with higher blood pressure.</p><p><b>METHODS</b>A single blind placebo-controlled trial was carried out for two years in 220 adolescents with higher blood pressure, aged 18 - 22 years, who were randomly divided into supplementary group (n = 110) and control group (n = 110). Each of the subjects in the supplementary group and their family members was given 10 mmol of potassium and 10 mmol of calcium mixed in their table salt daily for 24 months.</p><p><b>RESULTS</b>Night urinary sodium and potassium excretion increased (urinary Na(+), P < 0.05; urinary K(+), P < 0.01) and blood pressure lowered by 5.3 mm Hg/1.8 mm Hg in average from the baseline in the supplementary group two years after potassium and calcium supplementation, as compared with that in the control group increased by (1.3/1.7) mm Hg.</p><p><b>CONCLUSIONS</b>Adequate supplement of potassium and calcium in daily table salt intake was an effective way to prevent form hypertension and could promote their urinary sodium excretion and reduction of arterial blood pressure in adolescents with higher blood pressure.</p>