Vinay P, Lemieux G, Gougoux A
Curr Probl Clin Biochem. 1977;8:188-97.
The metabolism of cold and 14C-[U]-glutamine in isolated kidney tubules of normal rats was studied in vitro to establish the relative importance of glucose synthesis and complete oxidation to CO2 for the metabolism of this amino acid in vitro. These metabolic fates were estimated by drawing a complete balance of the nitrogens and of the carbon chains of the extracted glutamine and studying the formation of 14CO2 from 14C-glutamine. It was found that glucose production constitutes the major fate for glutamine metabolism with 1 mM glutamine and that glutamine oxidation constitutes less than 20% of the metabolic fate of the carbon skeleton of this amino acid. With 5 or 10 mM glutamine however, the maximal oxidation to CO2 becomes more important (25%).
为确定葡萄糖合成和完全氧化为二氧化碳在体外对该氨基酸代谢的相对重要性，对正常大鼠离体肾小管中冷态和14C-[U]-谷氨酰胺的代谢进行了体外研究。通过对提取的谷氨酰胺的氮和碳链进行完全平衡分析，并研究14C-谷氨酰胺生成14CO2的情况，来评估这些代谢去向。结果发现，对于1 mM谷氨酰胺，葡萄糖生成是谷氨酰胺代谢的主要去向，而谷氨酰胺氧化占该氨基酸碳骨架代谢去向的比例不到20%。然而，对于5或10 mM谷氨酰胺，最大程度氧化为二氧化碳变得更为重要（25%）。
