Meyer M, Koeppe R A, Frey K A, Foster N L, Kuhl D E
Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor.
Arch Neurol. 1995 Mar;52(3):314-7. doi: 10.1001/archneur.1995.00540270110027.
To evaluate the integrity of neurons and neuropil in metabolically affected association cortices of patients with Alzheimer's disease by measuring central benzodiazepine binding sites with the use of positron emission tomography.
In patients with Alzheimer's disease, we determined the cerebral distribution of flumazenil tagged with carbon 11 ([11C]flumazenil), a ligand that binds to the gamma-aminobutyric acid A (GABAA) receptor complex, and the distribution of fludeoxyglucose tagged with fluorine 18 fludeoxyglucose F 18), a measure of local cerebral glucose metabolism. Tracer kinetic analysis was applied to quantify data in regions of interest. These data were compared with those of normal control subjects.
Patients with probable Alzheimer's disease ([11C]flumazenil, n = 13; fludeoxyglucose F 18, n = 11) and normal elderly control subjects ([11C]flumazenil, n = 6; fludeoxyglucose F 18, n = 10).
Significant decreases of the [11C]flumazenil transport rate were found in hypometabolic parietal and temporal association cortices, but [11C]flumazenil binding was not significantly decreased.
When measured in living patients, association cortical benzodiazepine binding sites are relatively preserved, suggesting structurally intact cortical neuropil underlying the glucose hypometabolism identified in Alzheimer's disease.
通过使用正电子发射断层扫描测量中枢苯二氮䓬结合位点，评估阿尔茨海默病患者代谢受影响的联合皮质中神经元和神经纤维网的完整性。
在阿尔茨海默病患者中，我们测定了标记有碳11的氟马西尼（[11C]氟马西尼）的脑部分布，氟马西尼是一种与γ-氨基丁酸A（GABAA）受体复合物结合的配体，以及标记有氟18的氟脱氧葡萄糖（氟脱氧葡萄糖F 18）的分布，后者是局部脑葡萄糖代谢的一种测量指标。应用示踪动力学分析对感兴趣区域的数据进行量化。将这些数据与正常对照受试者的数据进行比较。
可能患有阿尔茨海默病的患者（[11C]氟马西尼组，n = 13；氟脱氧葡萄糖F 18组，n = 11）和正常老年对照受试者（[11C]氟马西尼组，n = 6；氟脱氧葡萄糖F 18组，n = 10）。
在代谢减低的顶叶和颞叶联合皮质中发现[11C]氟马西尼转运速率显著降低，但[11C]氟马西尼结合未显著降低。
在活体患者中测量时，联合皮质苯二氮䓬结合位点相对保留，这表明在阿尔茨海默病中确定的葡萄糖代谢减低的基础上，皮质神经纤维网结构完整。
