Barzilai N, Karnieli E, Barzilai D, Cohen P
Endocrine Institute, Rambam Medical Center, Haifa, Israel.
Horm Metab Res. 1993 Jul;25(7):382-5. doi: 10.1055/s-2007-1002124.
Insulin is known to decrease plasma levels of both glucose and amino acids. We have designed a study to examine whether in hyperthyroidism, where insulin sensitivity is changed, correlation between glucose disposal and amino acids levels is maintained. We studied 5 normal (N) and 5 hyperthyroid (HTD) subjects, and measured glucose disposal rate and serum levels of plasma amino acids before and during insulin infusion utilizing the euglycemic hyperinsulinemic clamp technique. Insulin was effective in decreasing the levels of all amino acids in the plasma of all subjects. The mean amino acid decrease in response to insulin infusion rate of 10 mu/kg/min was 35 +/- 3% in N and 50 +/- 3% in HTD. The half maximally effective dose of insulin on glucose disposal was 43 +/- 3 and 69 +/- 9 uU/ml in N and HTD respectively (p < 0.05). The half maximally effective dose of insulin on decreasing plasma amino acids was 37 +/- 7 and 75 +/- 5 uU/ml in N and HTD respectively (p < 0.01). The concentration of insulin giving a half maximal effect on serum amino acids correlated with the half-maximally effective dose on glucose disposal rate (r = 0.72, p < 0.01). The maximal effect on total amino acid levels correlated with maximal glucose disposal (r = 0.76, p < 0.001). Similar results were observed with branched chain amino acids. We conclude that in hyperthyroidism glucose disposal and decrease in amino acids levels are closely correlated as in healthy subjects. This also confirms the association between glucose disposal and amino acids levels in a variety of insulin sensitive and resistant states.
已知胰岛素可降低血浆葡萄糖和氨基酸水平。我们设计了一项研究，以检验在胰岛素敏感性发生变化的甲状腺功能亢进症中，葡萄糖代谢与氨基酸水平之间的相关性是否仍然存在。我们研究了5名正常（N）受试者和5名甲状腺功能亢进（HTD）受试者，并在胰岛素输注前和输注期间，采用正常血糖高胰岛素钳夹技术测量了葡萄糖代谢率和血浆氨基酸水平。胰岛素可有效降低所有受试者血浆中所有氨基酸的水平。在胰岛素输注速率为10 μU/kg/min时，N组受试者氨基酸平均降低35±3%，HTD组受试者降低50±3%。胰岛素对葡萄糖代谢的半数最大有效剂量在N组和HTD组分别为43±3和69±9 μU/ml（p<0.05）。胰岛素对降低血浆氨基酸的半数最大有效剂量在N组和HTD组分别为37±7和75±5 μU/ml（p<0.01）。对血清氨基酸产生半数最大效应的胰岛素浓度与对葡萄糖代谢率的半数最大有效剂量相关（r = 0.72，p<0.01）。对总氨基酸水平的最大效应与最大葡萄糖代谢相关（r = 0.76，p<0.001）。支链氨基酸也观察到类似结果。我们得出结论，在甲状腺功能亢进症中，与健康受试者一样，葡萄糖代谢与氨基酸水平的降低密切相关。这也证实了在各种胰岛素敏感和抵抗状态下，葡萄糖代谢与氨基酸水平之间的关联。
