Dohm G L, Beecher G R, Warren R Q, Williams R T
J Appl Physiol Respir Environ Exerc Physiol. 1981 Jan;50(1):41-4. doi: 10.1152/jappl.1981.50.1.41.
Levels of free amino acids in muscle, liver, and plasma were measured in rats that had either swum (1 or 2 h) or run (until exhausted). Exercise lowered alanine levels in all three tissues except for liver of exhausted rats. Exercise decreased the plasma levels of the acidic amino acids and their amides. Glutamate and glutamine levels were depressed in muscle, and the glutamine level was lowered in liver by exercise. Aspartate concentration was lowered by exercise in liver but elevated in muscle. The branched-chain amino acids were generally elevated by exercise as were tyrosine, phenylalanine, methionine, and lysine. Plasma 3-methylhistidine concentration was also elevated by an exercise bout. The changes observed in the amino acid contents of muscle, liver, and plasma are consistent with the increase in protein degradation during exercise that we previously reported. The lowered levels of some amino acids (e.g., alanine, glutamine, glutamate) seem to suggest that amino acid catabolism and/or gluconeogenesis is increased by exercise.
对游泳（1或2小时）或跑步（直至精疲力竭）的大鼠的肌肉、肝脏和血浆中的游离氨基酸水平进行了测量。运动降低了所有三种组织中的丙氨酸水平，但精疲力竭大鼠的肝脏除外。运动降低了血浆中酸性氨基酸及其酰胺的水平。运动使肌肉中的谷氨酸和谷氨酰胺水平降低，肝脏中的谷氨酰胺水平降低。运动使肝脏中的天冬氨酸浓度降低，但使肌肉中的天冬氨酸浓度升高。支链氨基酸以及酪氨酸、苯丙氨酸、蛋氨酸和赖氨酸通常因运动而升高。一次运动也会使血浆3-甲基组氨酸浓度升高。在肌肉、肝脏和血浆中观察到的氨基酸含量变化与我们之前报道的运动期间蛋白质降解增加一致。某些氨基酸（如丙氨酸、谷氨酰胺、谷氨酸）水平的降低似乎表明运动增加了氨基酸分解代谢和/或糖异生作用。
