Cambier D, Pessac B
INSERM U178, Unité de Recherches sur la Différenciation et la Neuroendocrinologie de Cellules Digestives, Villejuif, France.
J Neurochem. 1989 Aug;53(2):551-5. doi: 10.1111/j.1471-4159.1989.tb07368.x.
To investigate the role of astrocytes in the metabolism of glutamate, the neurotransmitter of the granule cells of the cerebellar cortex, we have analyzed various parameters related to the synthesis of glutamate in astroglial cell clones that may be the in vitro counterparts of the cerebellar astrocytes. The "fibrous"-like clone spontaneously released large quantities of glutamate, even in the absence of glutamine in the culture medium, but did not release alanine. In contrast, the "Golgi-Bergmann"-like cells released alanine but not glutamate, whereas the "velate-protoplasmic"-like astrocytes released little glutamate and alanine. However, the glutamate oxaloacetate transaminase and glutamate pyruvate transaminase activities of the three astroglial cell lines, measured in the direction of glutamate synthesis, were comparable. In addition, the "velate protoplasmic" and "Golgi-Bergmann" clones did not consume glutamine present at 2 mM in the culture medium. These data suggest that the different types of in vivo cerebellar astrocytes may have distinct roles regarding glutamate-glutamine metabolism.
为了研究星形胶质细胞在小脑皮质颗粒细胞神经递质谷氨酸代谢中的作用，我们分析了与谷氨酸合成相关的各种参数，这些参数来自可能是小脑星形胶质细胞体外对应物的星形胶质细胞克隆。“纤维样”克隆即使在培养基中没有谷氨酰胺的情况下也会自发释放大量谷氨酸，但不释放丙氨酸。相比之下，“高尔基 - 伯格曼样”细胞释放丙氨酸但不释放谷氨酸，而“边缘 - 原浆样”星形胶质细胞释放的谷氨酸和丙氨酸很少。然而，在谷氨酸合成方向上测量的三种星形胶质细胞系的谷氨酸草酰乙酸转氨酶和谷氨酸丙酮酸转氨酶活性相当。此外，“边缘原浆样”和“高尔基 - 伯格曼样”克隆不消耗培养基中2 mM的谷氨酰胺。这些数据表明，体内不同类型的小脑星形胶质细胞在谷氨酸 - 谷氨酰胺代谢方面可能具有不同的作用。
