Korzon-Burakowska A, Hopkins D, Matyka K, Lomas J, Pernet A, Macdonald I, Amiel S
Department of Medicine, King's College School of Medicine and Dentistry, London, UK.
Diabetes Care. 1998 Feb;21(2):283-90. doi: 10.2337/diacare.21.2.283.
To determine the effects of glycemic control on the counterregulatory responses to hypoglycemia in type 2 diabetes.
Seven poorly controlled type 2 diabetes patients (mean HbA1c, 11.3 +/- 1.1%) were studied by stepped hyperinsulinemic hypoglycemic clamp (nadir, 2.4 mmol/l) before and after improving glycemic control with insulin treatment. Counterregulatory hormones, symptoms, and four-choice reaction time were measured at each glucose plateau.
In patients with poorly controlled type 2 diabetes, counterregulatory hormone responses began at higher plasma glucose levels than did those in healthy subjects (epinephrine, 4.4 +/- 0.2 vs. 3.7 +/- 0.2 mmol/l, P = 0.011). After significant improvement in glycemic control (mean HbA1c, 8.1 +/- 0.9%, P < 0.001) was achieved without severe hypoglycemia, hormonal responses started at much lower plasma glucose levels (e.g., epinephrine, 3.5 +/- 0.3 mmol/l, P = 0.005) and were significantly reduced in magnitude (e.g., area under epinephrine response curve, 306 +/- 93 vs. 690 +/- 107 nmol.min-1.l-1, P = 0.012). This was accompanied by a change in the plasma glucose threshold at which hypoglycemic symptoms first developed from 3.6 +/- 0.2 to 3.0 +/- 0.2 mmol/l (P = 0.019). In contrast, the plasma glucose threshold at which four-choice reaction time deteriorated did not change significantly (3.1 +/- 0.1 vs. 2.9 +/- 0.1 mmol/l, P = 0.125).
Counterregulatory responses begin at normoglycemia in poorly controlled type 2 diabetes. Improving glycemic control with insulin therapy normalizes hormonal responses but lowers the plasma glucose levels at which hypoglycemic symptoms develop to levels associated with impairment of four-choice reaction time, a marker of cognitive function. This process potentially increases the risk of severe hypoglycemia, but to a lesser extent than occurs in type 1 disease.
确定血糖控制对2型糖尿病患者低血糖反应性调节反应的影响。
对7例血糖控制不佳的2型糖尿病患者（平均糖化血红蛋白[HbA1c]，11.3±1.1%）在胰岛素治疗改善血糖控制前后，通过逐步高胰岛素低血糖钳夹试验（最低点，2.4 mmol/L）进行研究。在每个血糖平台期测量反应性调节激素、症状及四选一反应时间。
血糖控制不佳的2型糖尿病患者，反应性调节激素反应开始时的血浆葡萄糖水平高于健康受试者（肾上腺素，4.4±0.2 vs. 3.7±0.2 mmol/L，P = 0.011）。在未发生严重低血糖的情况下血糖控制显著改善（平均HbA1c，8.1±0.9%，P < 0.001）后，激素反应开始时的血浆葡萄糖水平大幅降低（如肾上腺素，3.5±0.3 mmol/L，P = 0.005），且反应幅度显著降低（如肾上腺素反应曲线下面积，306±93 vs. 690±107 nmol·min-1·l-1，P = 0.012）。同时，首次出现低血糖症状时的血浆葡萄糖阈值从3.6±0.2降至3.0±0.2 mmol/L（P = 0.019）。相比之下，四选一反应时间变差时的血浆葡萄糖阈值无显著变化（3.1±0.1 vs. 2.9±0.1 mmol/L，P = 0.125）。
血糖控制不佳的2型糖尿病患者，反应性调节反应在正常血糖水平时就已开始。胰岛素治疗改善血糖控制可使激素反应正常化，但会将出现低血糖症状时的血浆葡萄糖水平降低至与四选一反应时间受损（认知功能的一个指标）相关的水平。这一过程可能会增加严重低血糖的风险，但程度低于1型糖尿病。
