Haaparanta Merja, Paul Robert, Grönroos Tove, Bergman Jörgen, Kämäräinen Eeva-Liisa, Solin Olof
Turku PET Centre, Medicity Research Laboratory/PET, Tykistokatu 6 A, FIN 20520 Turku, Finland.
Life Sci. 2003 Aug 1;73(11):1437-51. doi: 10.1016/s0024-3205(03)00470-3.
A combination of microdialysis (MD) and 2-[18F ]fluoro-2-deoxy-D-glucose (FDG) was used to assess FDG uptake, phosphorylation and the glucose metabolic index (Rg') in certain tissues of fed and fasting anesthetized Sprague-Dawley rats which received an i.v. bolus injection of insulin or saline during the course of the study. The relative recovery for FDG for the MD probes was also measured as a function of flow rate and temperature. The elimination half-life (T(1/2 FDG)) of FDG from the plasma and the extracellular fluid of muscle and liver was studied with MD. The phosphorylation of FDG in muscle, liver, subcutaneous fat and mesenteric fat from homogenates of these tissues was analyzed by a radioHPLC-method and the Rg' was calculated. The results show that the nutritional status does not affect the T(1/2 FDG), the total uptake of FDG 6-phosphate or the Rg' values in the studied tissues at ambient glucose. Insulin stimulation decreased T(1/2 FDG), and increased the total FDG 6-P accumulation and Rg' in the muscle of fed and fasted rats. In adipose tissues the insulin stimulation enhanced the phosphorylation but in muscle the proportion of FDG 6-P remained unchanged. Rg' in adipose tissue was higher after insulin administration in fed rats than without insulin but with fasted rats there were no differences in Rg' values with or without insulin, although the proportion of FDG 6-P did increase. The Rg' values for the livers were unaffected by any of the manipulations, but fasted rats accumulated proportionately more FDG 6-P after insulin administration than did fed rats. These results indicate that the combination of MD and FDG is a valuable and reliable tool when studying glucose metabolism in physiological and pathological models in vivo.
采用微透析（MD）和2-[¹⁸F]氟-2-脱氧-D-葡萄糖（FDG）相结合的方法，对在研究过程中接受静脉推注胰岛素或生理盐水的麻醉状态下的食饵性和禁食性Sprague-Dawley大鼠的某些组织中的FDG摄取、磷酸化及葡萄糖代谢指数（Rg'）进行评估。还测定了MD探针中FDG的相对回收率与流速和温度的函数关系。用MD研究了FDG从血浆以及肌肉和肝脏细胞外液中的消除半衰期（T₁/₂ FDG）。通过放射性高效液相色谱法分析了这些组织匀浆中肌肉、肝脏、皮下脂肪和肠系膜脂肪中FDG的磷酸化情况，并计算了Rg'。结果表明，在环境葡萄糖水平下，营养状态不影响所研究组织中的T₁/₂ FDG、6-磷酸-FDG的总摄取量或Rg'值。胰岛素刺激降低了T₁/₂ FDG，并增加了食饵性和禁食性大鼠肌肉中6-磷酸-FDG的总蓄积量及Rg'。在脂肪组织中，胰岛素刺激增强了磷酸化作用，但在肌肉中6-磷酸-FDG的比例保持不变。食饵性大鼠给予胰岛素后脂肪组织中的Rg'高于未给予胰岛素时，但禁食性大鼠给予胰岛素与否时Rg'值无差异，尽管6-磷酸-FDG的比例确实增加了。肝脏的Rg'值不受任何操作的影响，但禁食性大鼠给予胰岛素后比食饵性大鼠蓄积了相对更多的6-磷酸-FDG。这些结果表明，MD和FDG相结合是研究体内生理和病理模型中葡萄糖代谢的一种有价值且可靠的工具。
