Donovan D S, Solomon C G, Seely E W, Williams G H, Simonson D C
Endocrine-Hypertension Division, Brigham and Women's Hospital, Joslin Diabetes Center, Boston, Massachusetts.
Am J Physiol. 1993 May;264(5 Pt 1):E730-4. doi: 10.1152/ajpendo.1993.264.5.E730.
To examine the effects of sodium intake on insulin sensitivity, we performed euglycemic insulin clamp studies (40 mU.m-2.min-1) in eight healthy normotensive nondiabetic white males (age = 36 +/- 5 yr; wt = 66 +/- 3 kg) after 5 days on high (200 meq/day)- and low (10 meq/day)-sodium diets administered in random order. High sodium intake was associated with significantly greater urinary sodium excretion (160 +/- 7 vs. 8 +/- 2 meq/day; P < 0.0001), suppression of plasma aldosterone (7 +/- 3 vs. 38 +/- 6 ng/dl; P < 0.001) and renin (1.5 +/- 0.2 vs. 6.0 +/- 0.9 ng.ml-1.h-1; P < 0.005) levels, but no change in blood pressure (116 +/- 3/63 +/- 2 vs. 114 +/- 3/64 +/- 2 mmHg; P = not significant). The rate of glucose infusion during the clamp was significantly reduced during the high- vs. low-sodium diet (279 +/- 19 vs. 334 +/- 24 mg.m-2.min-1; P < 0.01). This impairment in insulin sensitivity was not related to changes in serum potassium, epinephrine, norepinephrine, cortisol, or growth hormone but was highly correlated with an increment in circulating free fatty acid levels during high sodium intake (r = 0.82, P < 0.05). These data suggest that 1) high sodium intake may exacerbate insulin resistance by increasing circulating free fatty acids, and 2) differences in sodium intake may influence measures of insulin sensitivity in other disease states.
为研究钠摄入对胰岛素敏感性的影响，我们对8名健康的血压正常、非糖尿病的白人男性（年龄 = 36 ± 5岁；体重 = 66 ± 3千克）进行了正常血糖胰岛素钳夹试验（40 mU·m⁻²·min⁻¹），试验前他们按随机顺序分别接受了5天的高钠（200 meq/天）和低钠（10 meq/天）饮食。高钠摄入与尿钠排泄显著增加相关（160 ± 7 vs. 8 ± 2 meq/天；P < 0.0001），血浆醛固酮（7 ± 3 vs. 38 ± 6 ng/dl；P < 0.001）和肾素（1.5 ± 0.2 vs. 6.0 ± 0.9 ng·ml⁻¹·h⁻¹；P < 0.005）水平受到抑制，但血压无变化（116 ± 3/63 ± 2 vs. 114 ± 3/64 ± 2 mmHg；P = 无显著差异）。与低钠饮食相比，高钠饮食期间钳夹试验中的葡萄糖输注速率显著降低（279 ± 19 vs. 334 ± 24 mg·m⁻²·min⁻¹；P < 0.01）。胰岛素敏感性的这种损害与血清钾、肾上腺素、去甲肾上腺素、皮质醇或生长激素的变化无关，但与高钠摄入期间循环游离脂肪酸水平的升高高度相关（r = 0.82，P < 0.05）。这些数据表明：1）高钠摄入可能通过增加循环游离脂肪酸来加剧胰岛素抵抗；2）钠摄入量的差异可能影响其他疾病状态下胰岛素敏感性的测量。
