Grill V
Department of Endocrinology, Karolinska Hospital, Stockholm, Sweden.
Ann Med. 1990 Jun;22(3):171-6. doi: 10.3109/07853899009147264.
[U-11-C]-glucose and positron emission tomography was used to evaluate transport and oxidative metabolism of glucose in the brain of non-diabetic and insulin dependent diabetic (IDDM) subjects. These results were compared with results obtained by the Fick principle. Blood glucose was regulated by a Biostator controlled glucose infusion during a constant insulin infusion. [U-11-C]-glucose was injected during normoglycemia as well as during moderate hypoglycemia. The tracer data were analysed using a three compartment model with a fixed correction for [11-C]-CO2 egress. During normoglycemia the influx rate constant (k1) and blood brain glucose flux of the two groups were similar. During hypoglycemia k1 increased significantly and to the same extent in both groups. During normoglycemia the tracer calculated metabolism of glucose was higher in the brain of non-diabetic than of diabetic subjects. When measured by the Fick principle the net uptake of glucose was broadly the same for the groups. During normoglycemia the molar ratio of O2 to glucose uptake was, however, lower in IDDM than in non-diabetic subjects (4.67 vs 5.50, P less than 0.05, Wilcoxon test). A significant release of lactate and pyruvate was seen in IDDM but not in non-diabetic subjects. The results imply that a larger fraction of glucose is non-oxidatively metabolized in IDDM than in non-diabetic subjects.
采用[U-11-C]-葡萄糖和正电子发射断层扫描技术评估非糖尿病和胰岛素依赖型糖尿病（IDDM）患者大脑中葡萄糖的转运和氧化代谢情况。将这些结果与通过菲克原理获得的结果进行比较。在持续输注胰岛素期间，通过生物调节器控制葡萄糖输注来调节血糖。在血糖正常以及中度低血糖期间注射[U-11-C]-葡萄糖。使用三室模型对示踪剂数据进行分析，并对[11-C]-CO2流出进行固定校正。在血糖正常期间，两组的流入速率常数（k1）和血脑葡萄糖通量相似。在低血糖期间，两组的k1均显著增加且增加程度相同。在血糖正常期间，示踪剂计算得出的非糖尿病患者大脑中葡萄糖的代谢高于糖尿病患者。当通过菲克原理测量时，两组的葡萄糖净摄取大致相同。然而，在血糖正常期间，IDDM患者的O2与葡萄糖摄取的摩尔比低于非糖尿病患者（4.67对5.50，P<0.05，威尔科克森检验）。在IDDM患者中观察到乳酸和丙酮酸的显著释放，而在非糖尿病患者中未观察到。结果表明，与非糖尿病患者相比，IDDM患者中更大比例的葡萄糖进行非氧化代谢。
