NA+/K+ INTAKE AND CV REACTIVITY IN BLACK ADOLESCENTS

美国黑人高血压患病率已达 流行比例，是世界上最高的种族之一 世界(1)。由于高血压的先兆开始于儿童时期(2)，理想的 预防的人群是儿童和青少年。以前的研究 已经证明黑人儿童表现出更大的心血管(CV) 反应性(对压力的血压升高)和更高水平 与白人儿童相比，睡眠时血压升高(3-4)。考虑到 高血压在黑人成年人中的患病率很高，心血管反应性增加和 睡眠时血压升高可能是高血压的重要危险因素或标志。 黑人儿童高血压的早期发展。 一些研究人员认为，钠(Na+)敏感性 (改变血压以改变钠离子摄入量)也是血压的一个重要因素 监管。黑人更有可能表现出钠离子敏感性(SS)BP 回答比白人多(5比7)。此外，饮食方面的研究 干预措施表明，尤其是黑人，他们的人数有所减少 对低钠饮食(5-7)的反应。然而，合规性 低钠饮食在永久改变生活方式方面可能是 很难，尤其是对孩子们来说。最近，调查人员已经 表明增加饮食中的钾(K+)也可能有益于 对随意血压的影响，特别是对SS个体(8-11)。 从理论上讲，坚持高K+饮食对 儿童比坚持低钠饮食要好。支持这种观点的证据 高K+饮食对血压的有益影响来自两项动物研究 (8-10)和K+补充研究(11-15)。此外，校长 调查人员最近完成了一项初步研究(16)，证明了 显著增加一组黑人青少年的膳食K+ 收缩压(S)和舒张压(D)反应性从治疗前降低到 节食后。动态血压与(A)BP关系的研究 模式和电解质排泄还没有显示出联系 一组受试者醒着或睡着时K+摄入与ABP模式之间的关系 黑人和白人儿童(17)；然而，有必要进行进一步的研究 确定增加膳食K+是否与ABP的差异有关 SS与抗Na+(SR)个体的模式。该计划的目的是 目前的建议是确定高K+饮食的影响 干预对SS患者心血管反应性、ABP和偶然性BP的影响 血压正常的老年黑人青少年。

The prevalence of essential hypertension (EH) in U.S. blacks has reached epidemic proportions and is among the highest of any racial group in the world (1). Since the precursors of EH begin in childhood (2), the ideal population for prevention is children and adolescents. Previous research has demonstrated that black children show greater cardiovascular (CV) reactivity (increases in blood pressure (BP) to stress) and higher levels of BP while asleep as compared to white children (3-4). Given that the prevalence of EH is great among black adults, increased CV reactivity and elevated BP while asleep may be important risk factors or markers for the early development of EH in black children. A number of investigators have suggested that sodium (Na+) sensitivity (changes in BP to altering Na+ intake) is also an important factor in BP regulation. Blacks are more likely to show Na+ sensitive (SS) BP responses than whites (5-7). In addition, research on dietary interventions has indicated that blacks, in particular, show reductions in casual BP in response to low Na+ diets (5-7). However, compliance with low Na+ diets in terms of making permanent lifestyle changes may be difficult, especially for children. More recently, investigators have shown that increasing dietary potassium (K+) may also have beneficial effects on casual BP, especially in SS Individuals (8-11). Theoretically, adhering to a high K+ diet should be much easier for children than adhering to a low Na+ diet. Evidence supporting the beneficial effect of a high K+ diet on BP comes from both animal research (8-10) and K+ supplement studies (11-15). In addition, the Principal Investigator recently completed a pilot study (16) which demonstrated that Increasing dietary K+ in a group of black adolescents significantly decreased both systolic (S) and diastolic (D) BP reactivity from pre- to post-diet. Research on the relationship between ambulatory (A) BP patterns and electrolyte excretion has not demonstrated an association between K+ intake and ABP patterns while awake or asleep in a group of black and white children (17); however, further research Is warranted to determine if increasing dietary K+ is associated with differences in ABP patterns in SS versus Na+ resistant (SR) individuals. The purpose of the present proposal is to determine the effects of a high K+ dietary intervention on changing CV reactivity, ABP, and casual BP In SS versus SR black normotensive adolescents.