MULTINUCLEAR NMR-STUDIES ON THE ENERGY-METABOLISM OF GLIAL AND NEURONAL CELLS
MULTINUCLEAR NMR-STUDIES ON THE ENERGY-METABOLISM OF GLIAL AND NEURONAL CELLS
复制标题
DOI：
10.1159/000111347
复制
发表时间：
1993-05-01
影响因子：
2.9
通讯作者：
LEIBFRITZ, D
中科院分区：
文献类型：
--
作者：
BRAND, A;RICHTERLANDSBERG, C;LEIBFRITZ, D
在这项多核NMR研究中，肌醇被确定为体内NMR研究的神经胶质特异性标志物。异常高的肌醇浓度可能参与了星形胶质细胞的肌醇调节系统。初级星形胶质细胞也合成和输出大量的亚牛磺酸，牛磺酸合成的中间体。牛磺酸-另一种渗透剂-由星形胶质细胞而不是初级神经元从半胱氨酸合成。牛磺酸以及亚牛磺酸由细胞外介质中的神经元积累。用2-C-13丙酮酸盐的C-13 NMR标记结果表明，大鼠原代神经元中回补途径有相当大的贡献。活性仅为原代星形胶质细胞活性的一半。丙酮酸羧化酶/苹果酸酶活性与丙酮酸脱氢酶活性的比值反映了成熟程度。谷氨酸和谷氨酰胺的C-13同位素比例对于纯星形胶质细胞培养物是不同的。因此，单独从完整脑研究中获得的谷氨酸与谷氨酰胺的不同同位素异构体比率不能证明脑中的TCA循环比较。最后，原代星形胶质细胞中的PCr/ATP比率比原代神经元中的高3倍。在从缺血性损伤中恢复的情况下，必须考虑这一点。
In this multinuclear NMR study myo inositol is identified as a glia-specific marker for in vivo NMR studies. The unusually high inositol concentration may participate in the osmoregulatory system in astrocytes. Primary astrocytes also synthesize and export high amounts of hypotaurine, an intermediate of taurine synthesis. Taurine - another osmolyte - is synthesized from cysteine by astrocytes but not by primary neurons. Taurine as well as hypotaurine is accumulated by neurons from the extracellular medium. C-13 NMR labelling results with 2-C-13 pyruvate indicate a considerable contribution of the anaplerotic pathway in primary neurons from rat. The activity is only half of the activity in primary astrocytes. The ratio of pyruvate carboxylase/malic enzyme activity Versus pyruvate dehydrogenase activity reflects the degree of maturation. The C-13 isotopomer ratio of glutamate and glutamine is different for pure astrocyte cultures. Therefore, the different isotopomer ratios of glutamate to glutamine obtained from intact brain studies alone do not prove TCA cycle compartimentation in the brain. Finally, the PCr/ATP ratio in primary astrocytes is 3 times higher than in primary neurons. This has to be considered in case of recovery from ischemic insults.