Moxley R T, Kingston W J, Minaker K L, Corbett A J, Rowe J W
Clin Sci (Lond). 1986 Oct;71(4):429-36. doi: 10.1042/cs0710429.
To quantify the degree of whole body insulin resistance in patients with myotonic dystrophy and to determine if these same patients display signs of a whole body decrease in the action of insulin on amino acid uptake and glucose disposal, three separate 120 min studies employing the euglycaemic insulin clamp technique (20, 80 and 200 m-units min-1 m-2) were performed on five ambulatory patients with myotonic dystrophy. The results were compared with findings obtained in identical studies in 21 normal volunteers. Myotonic dystrophy patients showed a slower, less marked decline in the serum concentration of insulin sensitive amino acids (threonine, valine, leucine, isoleucine, tyrosine, phenylalanine) during all three insulin infusions compared with normals. The greatest difference occurred at the low physiological elevations of insulin produced by the 20 m-units min-1 m-2 infusion. Alanine levels fell significantly below baseline in patients with myotonic dystrophy after 60 and 120 min of insulin infusion with all three rates of insulin infusion. Normal subjects had only a minimal, insignificant decline in arterialized alanine concentrations during the three different insulin infusions. Creatinine adjusted rates of whole body glucose disposal were 30-40% lower in the myotonic dystrophy group at all three doses of insulin compared with the normals. This demonstrates that their insulin resistance was not due simply to a reduction in muscle mass. The overall pattern of findings in these studies of patients with myotonic dystrophy indicates that there is a whole body derangement in the regulation of circulating amino acid levels by insulin as well as a marked decrease in the action of this hormone in stimulating glucose uptake by target tissues.
为了量化强直性肌营养不良患者全身胰岛素抵抗的程度，并确定这些患者是否表现出胰岛素对氨基酸摄取和葡萄糖代谢作用的全身下降迹象，我们对5名非卧床强直性肌营养不良患者进行了三项独立的120分钟研究，采用正常血糖胰岛素钳夹技术（20、80和200 m单位·分钟⁻¹·平方米⁻²）。将结果与21名正常志愿者在相同研究中的发现进行比较。与正常人相比，强直性肌营养不良患者在所有三次胰岛素输注期间，胰岛素敏感氨基酸（苏氨酸、缬氨酸、亮氨酸、异亮氨酸、酪氨酸、苯丙氨酸）的血清浓度下降较慢且不太明显。最大差异出现在20 m单位·分钟⁻¹·平方米⁻²输注产生的低生理胰岛素升高水平时。在所有三种胰岛素输注速率下，胰岛素输注60分钟和120分钟后，强直性肌营养不良患者的丙氨酸水平显著低于基线。在三种不同的胰岛素输注期间，正常受试者的动脉化丙氨酸浓度仅有轻微的、不显著的下降。在所有三种胰岛素剂量下，强直性肌营养不良组的肌酐校正全身葡萄糖代谢率比正常人低30 - 40%。这表明他们的胰岛素抵抗并非仅仅由于肌肉量减少。这些对强直性肌营养不良患者的研究中的总体发现模式表明，胰岛素对循环氨基酸水平的调节存在全身紊乱，并且该激素在刺激靶组织摄取葡萄糖方面的作用显著降低。
