BRAIN GLUCOSE TRANSPORT IN SUBJECTS & PATIENTS WITH DIABETES FOLLOWING HYPOGLYC

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 虽然众所周知，反复低血糖会导致不自觉的低血糖，但导致低血糖的机制尚不清楚。一种假说是，反复发生的低血糖会改变大脑的葡萄糖运输或代谢。我们测量了葡萄糖钳夹期间的稳态脑葡萄糖浓度，以确定1型糖尿病和低血糖昏迷的受试者在暴露于反复低血糖后是否改变了大脑的葡萄糖运输或代谢。我们比较了14名有糖尿病和低血糖意识的受试者和27名健康对照组受试者。在相同代谢条件下，用生长抑素和胰岛素进行高血糖钳夹(血糖=16.7 mm o l/L)，在4特斯拉的活体1H核磁共振波谱测定脑内葡萄糖浓度。在相同条件下，无意识低血糖的1型糖尿病患者的脑葡萄糖浓度显著高于对照组(5.5vs.4.7±0.1mol/g湿重，P=0.016)。这些数据表明，反复低血糖可能会导致脑部葡萄糖运输或代谢的改变。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Although it is well established that recurrent hypoglycemia leads to hypoglycemia unawareness, the mechanisms responsible for this are unknown. One hypothesis is that recurrent hypoglycemia alters brain glucose transport or metabolism. We measured steady-state brain glucose concentrations during a glucose clamp to determine whether subjects with type 1 diabetes and hypoglycemia unawareness may have altered cerebral glucose transport or metabolism after exposure to recurrent hypoglycemia. We compared 14 subjects with diabetes and hypoglycemia unawareness to 27 healthy control subjects. Brain glucose concentrations were measured under similar metabolic conditions using in vivo 1H nuclear magnetic resonance (NMR) spectroscopy at 4 Tesla during a hyperglycemic clamp (plasma glucose = 16.7 mmol/l) with somatostatin and insulin. Subjects with type 1 diabetes and hypoglycemia unawareness had significantly higher brain glucose concentrations compared to that in controls under the same conditions (5.5 ¿ 0.3 vs. 4.7 ¿ 0.1 mol/g wet weight, P = 0.016). These data suggest that changes in brain glucose transport or metabolism may occur as a result of recurrent hypoglycemia