METHODOLOGICAL ASPECTS, DOSE-RESPONSE CHARACTERISTICS AND CAUSES OF INTERINDIVIDUAL VARIATION IN INSULIN STIMULATION OF LIMB BLOOD-FLOW IN NORMAL SUBJECTS
METHODOLOGICAL ASPECTS, DOSE-RESPONSE CHARACTERISTICS AND CAUSES OF INTERINDIVIDUAL VARIATION IN INSULIN STIMULATION OF LIMB BLOOD-FLOW IN NORMAL SUBJECTS
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DOI：
10.1007/bf00400724
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发表时间：
1995-05-01
期刊：
影响因子：
8.2
通讯作者：
YKIJARVINEN, H
中科院分区：
文献类型：
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作者：
UTRIAINEN, T;MALMSTROM, R;YKIJARVINEN, H
为了解决胰岛素调节血流的一些争议，我们在20名正常受试者中进行了a）体积描记法、多普勒超声和激光多普勒血流测量的重复性研究（n = 7），B）测量前臂的胰岛素剂量-反应序贯研究（n = 7），（体积描记法）、腿部（多普勒超声）和皮肤（激光多普勒）血流（n = 12），和c）比较前臂（体积描记法）和小腿（体积描记法）血流的连续胰岛素剂量-反应研究（n = 8）。我们还寻找可能解释胰岛素血流量反应个体间差异的因素。在序贯胰岛素输注期间（每次2小时，61 +/-2，139 +/-6，462 +/-15 mU/l），前臂血流量分别增加17 +/-6，50 +/-14和113 +/-17%（步骤之间p <0.05或更少）。61 +/-2 mU/l胰岛素浓度的增加几乎不超过方法学变异（13 +/-2%）。与血流量的持续增加相反，葡萄糖动静脉差异在最低61 +/-2 mU/l胰岛素浓度时达到最大值（1.7 +/-0.2 mmol/l），此后保持恒定。当用体积描记法测定时，前臂和小腿对胰岛素的血流反应几乎相同。相比之下，只有27%的增加，检测到股动脉血流指数确定多普勒超声。前臂血流（每前臂体积）与相对前臂肌肉含量高度相关（平均59 +/-5%，范围24 - 81%），均为基底动脉（r = 0.86，p <0.001，n = 12），在所有胰岛素浓度下（r = 0.85 - 0.92，p <0.001），表明前臂肌肉的百分比解释了70 - 85%的血流量个体间差异。总之，1）生理胰岛素浓度主要通过增加葡萄糖提取来刺激葡萄糖摄取，而超生理胰岛素浓度主要通过增加血流量来增加前臂葡萄糖摄取。2)胰岛素刺激前臂和小腿血流量的剂量-反应特性是相似的，当确定与应变计体积描记。3)相对前臂肌肉含量是决定正常受试者基础前臂血流量及其对胰岛素反应的个体间差异的关键因素。
To resolve some of the controversy regarding insulin regulation of blood flow, we performed in 20 normal subjects a) a reproducibility study of plethysmographic, Doppler ultrasound and laser Doppler blood flow measurements (n = 7), b) a sequential insulin dose-response study with measurement of forearm (plethysmography), leg (Doppler ultrasound) and skin (laser Doppler) blood flow (n = 12), and c) a sequential insulin dose-response study with comparison of forearm (plethysmography) and calf (plethysmography) blood flow (n = 8). We also searched for factors which might explain the interindividual variation in the blood flow response to insulin. During sequential insulin infusions (2 h each, 61 +/- 2, 139 +/- 6, 462 +/- 15 mU/l), forearm blood flow increased by 17 +/- 6, 50 +/- 14 and 113 +/- 17% (p < 0.05 or less between steps), respectively. The increase at the 61 +/- 2 mU/l insulin concentration barely exceeded methodological variation (13 +/- 2%). In contrast to the continuous increase in blood flow, the glucose arterio venous difference reached its maximum (1.7 +/- 0.2 mmol/l) at the lowest 61 +/- 2 mU/l insulin concentration and remained constant thereafter. Forearm and calf blood flow responses to insulin were virtually identical when determined with plethysmography. In contrast, only a 27% increase was detected in femoral flow index as determined by Doppler ultrasound. Forearm blood flow (per forearm volume) was highly correlated with the relative forearm muscle content (mean 59 +/- 5%, range 24-81%) both basally (r = 0.86, p < 0.001, n = 12) and at all insulin concentrations (r = 0.85-0.92, p < 0.001) indicating that the percent of forearm that is muscle explains 70-85% of interindividual variation in blood flow. In conclusion 1) physiological insulin concentrations stimulate glucose uptake mainly by increasing glucose extraction while supraphysiological insulin concentrations increase forearm glucose uptake predominantly via increases in blood flow. 2) The dose-response characteristics of insulin stimulation of forearm and calf blood flow are similar when determined with strain-gauge plethysmography. 3) Relative forearm muscle content is a key factor in determining both basal forearm blood flow and the interindividual variation in its response to insulin in normal subjects.