GLUTAMINE-METABOLISM IN LYMPHOCYTES OF THE RAT
GLUTAMINE-METABOLISM IN LYMPHOCYTES OF THE RAT
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DOI：
10.1042/bj2120835
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发表时间：
1983-01-01
影响因子：
4.1
通讯作者：
NEWSHOLME, EA
中科院分区：
文献类型：
--
作者：
ARDAWI, MSM;NEWSHOLME, EA
研究了谷氨酰胺在静息和刀豆球蛋白-A [Con A]刺激的淋巴细胞中的代谢。在从大鼠肠系膜淋巴结分离的孵育淋巴细胞中，O2和谷氨酰胺利用率以及天冬氨酸产生率在60 min内与时间呈近似线性关系，腺嘌呤核苷酸浓度加上ATP/ADP或ATP/AMP浓度比在90 min内保持近似恒定。谷氨酰胺代谢的主要终产物为谷氨酸、天冬氨酸和氨：来自谷氨酰胺的碳可以贡献apprx。30%是呼吸。当葡萄糖和谷氨酰胺都呈现给细胞时，这两种物质的利用率增加。有证据表明谷氨酰胺对糖酵解的刺激可能部分是由于6-磷酸果糖激酶的激活。供体动物的饥饿增加了谷氨酰胺的利用率。磷酸烯醇式丙酮酸羧激酶抑制剂巯基吡啶甲酸降低谷氨酰胺利用率的28%，谷氨酸和氨的积累率下降，而乳酸，天冬氨酸和苹果酸的增加。丝裂原Con A增加谷氨酰胺利用率（约为0.001）。51%）。在培养的淋巴细胞中由Con A引起的[3 H]胸苷掺入DNA的速率在不存在谷氨酰胺的情况下非常低;它增加了约4-在1 μ M-谷氨酰胺时增加了10倍，在0.3mM-谷氨酰胺时达到最大。其他氨基酸和氨都不能代替谷氨酰胺。
The metabolism of glutamine in resting and concanavalin-A[Con A]-stimulated lymphocytes was investigated. In incubated lymphocytes isolated from rat mesenteric lymph nodes, the rates of O2 and glutamine utilization, and that of aspartate production were approximately linear with respect to time for 60 min, and the concentrations of adenine nucleotides plus the ATP/ADP or ATP/AMP concentration ratios remained approximately constant for 90 min. The major end products of glutamine metabolism were glutamate, aspartate and ammonia: the carbon from glutamine may contribute .apprx. 30% to respiration. When both glucose and glutamine were presented to the cells, the rates of utilization of both substances increased. Evidence was obtained that the stimulation of glycolysis by glutamine could be due, in part, to an activation of 6-phosphofructokinase. Starvation of the donor animal increased the rate of glutamine utilization. The phosphoenolpyruvate carboxykinase inhibitor mercaptopicolinate decreased the rate of glutamine utilization by 28%; the rates of accumulation of glutamate and ammonia were decreased, whereas those of lactate, aspartate and malate were increased. The mitogen Con A increased the rate of glutamine utilization (by .apprx. 51%). The rate of [3H]thymidine incorporation into DNA caused by Con A in cultured lymphocytes was very low in the absence of glutamine; it was increased .apprx. 4-fold at 1 .mu.M-glutamine and was maximal at 0.3 mM-glutamine. Neither other amino acids nor ammonia could replace glutamine.