背景:这项工作的目的是研究屏气潜水(BH-diving)训练课程后的血清氨基酸(AA)变化,包括能量需求,疲劳耐受性,一氧化氮(NO)的产生,抗氧化剂合成与低氧适应。12名受过训练的BH潜水员在公海训练期间接受了调查,并在训练前30分钟进行了血液采样。训练后30分钟和4小时。血清样品测定与能量需求相关的AA变化(丙氨酸,组氨酸,异亮氨酸,亮氨酸,赖氨酸,蛋氨酸,脯氨酸苏氨酸,缬氨酸),疲劳耐受性(鸟氨酸,苯丙氨酸,酪氨酸),一氧化氮生产(瓜氨酸),抗氧化剂合成(胱氨酸,谷氨酸,甘氨酸)和缺氧适应(丝氨酸,牛磺酸)。
结果:关于在体力劳动中用作能量支持的AA,我们发现,即使丙氨酸,所有研究的AA在T1时都有统计学上的显着下降,并且逐渐恢复到T2时的基础值,脯氨酸和苏氨酸此时仍显示出轻微的显着减少。此外,与AA相关的与体力劳动耐受性相关的变化显示,仅在T1时相对于潜水前值有统计学意义的下降,在T2时恢复到正常值。瓜氨酸,不参与生产,在T1和T2均显示出明显的显著降低。关于参与内源性抗氧化剂合成的AA,所调查的三种AA的行为是不同的:我们发现在T1和T2时,胱氨酸均有统计学上的显着增加,而甘氨酸则有统计学上的显着减少(T1和T2)。谷氨酸没有显示任何统计学差异。最后,我们发现在其他缺氧条件下研究的AA丝氨酸和牛磺酸(T1和T2)有统计学意义的下降。
结论:我们的数据似乎表明,能量代谢需求在很大程度上是由用作燃料代谢底物的AA支持的,并且也是疲劳耐受性。AA支持NO的产生和抗氧化剂的合成。最后,有一些有趣的数据与缺氧刺激有关,可以间接地证实肌肉装置在强烈的暴露条件下工作,尽管运动强度非常短/低,由于反复潜水造成的间歇性缺氧。
BACKGROUND: The aim of this work was to investigate the serum amino acid (AA) changes after a breath-hold diving (BH-diving) training session under several aspects including energy need, fatigue tolerance, nitric oxide (NO) production, antioxidant synthesis and hypoxia adaptation. Twelve trained BH-divers were investigated during an open sea training session and sampled for blood 30 min before the training session, 30 min and 4 h after the training session. Serum samples were assayed for AA changes related to energy request (alanine, histidine, isoleucine, leucine, lysine, methionine, proline threonine, valine), fatigue tolerance (ornithine, phenylalanine, tyrosine), nitric oxide production (citrulline), antioxidant synthesis (cystine, glutamate, glycine) and hypoxia adaptation (serine, taurine).
RESULTS: Concerning the AA used as an energy support during physical effort, we found statistically significant decreases for all the investigated AA at T1 and a gradual return to the basal value at T2 even if alanine, proline and theonine still showed a slight significant reduction at this time. Also, the changes related to the AA involved in tolerance to physical effort showed a statistically significant decrease only at T1 respect to pre-diving value and a returned to normal value at T2. Citrulline, involved in NO production, showed a clear significant reduction both at T1 and T2. Concerning AA involved in endogenous antioxidant synthesis, the behaviour of the three AA investigated is different: we found a statistically significant increase in cystine both at T1 and T2, while glycine showed a statistically significant reduction (T1 and T2). Glutamate did not show any statistical difference. Finally, we found a statistically significant decrease in the AA investigated in other hypoxia conditions serine and taurine (T1 and T2).
CONCLUSIONS: Our data seem to indicate that the energetic metabolic request is in large part supported by AA used as substrate for fuel metabolism and that also fatigue tolerance, NO production and antioxidant synthesis are supported by AA. Finally, there are interesting data related to the hypoxia stimulus that indirectly may confirm that the muscle apparatus works under strong exposure conditions notwithstanding the very short/low intensity of exercise, due to the intermittent hypoxia caused by repetitive diving.