The differences between the effects of oral potassium supplementation and magnesium supplementation on blood pressure and lipid metabolism in human subjects.

本研究的目的是研究补充钾(K)和补充镁(Mg)对血压和脂代谢的影响。在第一项研究中(由20名健康的青年受试者组成)，进行了交叉研究(研究I)，而第二项研究包括13名老年受试者(研究II)。在研究1中，受试者服用对照饮食(K2g，镁250 mg/d)，并分别接受口服镁(镁负荷：mg 411 mg/d)和补钾(K负荷：K 1.9g/d)，为期4周。研究II的受试者接受与研究I相同的治疗方案。K负荷后，舒张压显著降低。尿钾排泄量和钠排泄量(均以磨合值的百分比表示)与钾负荷呈显著负相关。在MG-LOAS中，尿去甲肾上腺素排泄量与尿镁排泄量(以磨合值的百分比表示)之间存在统计学上的显著负相关。由于24小时去甲肾上腺素排泄量的减少，收缩压也显著降低。补充镁后，LCAT在统计学上也有显著增加。在镁负荷下，LCAT水平和高密度脂蛋白之间存在显著的正相关，但在K负荷中则不存在。这些结果表明，镁负荷可能通过抑制肾上腺素能活动而降低血压，也可能通过促钠排钠来降低血压，而钾负荷可能通过钠尿来降低血压。此外，受试者在摄入镁后，通过激活LCAT，也可以改善血脂。

The aim of this study was to examine the differences between the effects of potassium (K) supplementation and magnesium (mg) supplementation on both blood pressure and lipid metabolism. In the first study (consisting of 20 healthy yound subjects), a cross-over study was performaed (Study I), while the second study consisting of 13 elderly subjects (study II). In study I,the subjects consumed a control diet (K 2g, Mg 250mg/day) with oral supplementation and all thus received oral Mg supplementation (Mg-load : Mg 411mg/day) and K supplementation (K-load : K 1.9g/day) afor 4 weeks, respectively. The subjects in study II received the same protocol as that in study I.The sysotolic blood pressure values significanlty decrased after the K-load. A significantly negative correlation was observed between the urinary K excretion and sodium excretion (both expressed as a precentage of the run-in value) on the K-load. In the Mg-loas, there was a statistically significant negative correlation between the values for urinary noradrenaline excretion and urinary Mg excretion (expressed as a percentage of teh run-in value). The systolinc blood pressure also significantly decreased due to a reduction of the 24h-noradrenaline excretion. A statistically significant increase in LCAT was also observed after Mg supplementation. A significantly posotive correlation was observed between the levels of LCAT and HDL in the Mg-load, but this did not occur in the K-load. These results suggest that the Mg-load may lower blood pressure by suppressing the adregergic activity and also by possibly inducing natriuresis, while the K-load may decrease blood pressure through natriuresis. In addition, the serum lipid also improved through the activation of lCAT in human subjects after an Mg-load.