Naval Submarine Medical Research Laboratory, Groton, CT, USA.
Nutr Metab (Lond). 2010 Apr 21;7:31. doi: 10.1186/1743-7075-7-31.
Skeletal muscle protein synthesis has generally been determined by the precursor:product labeling approach using labeled amino acids (e.g., [13C]leucine or [13C]-, [15N]-, or [2H]phenylalanine) as the tracers. Although reliable for determining rates of protein synthesis, this methodological approach requires experiments to be conducted in a controlled environment, and as a result, has limited our understanding of muscle protein renewal under free-living conditions over extended periods of time (i.e., integrative/cumulative assessments). An alternative tracer, 2H2O, has been successfully used to measure rates of muscle protein synthesis in mice, rats, fish and humans. Moreover, perturbations such as feeding and exercise have been included in these measurements without exclusion of common environmental and biological factors. In this review, we discuss the principle behind using 2H2O to measure muscle protein synthesis and highlight recent investigations that have examined the effects of feeding and exercise. The framework provided in this review should assist muscle biologists in designing experiments that advance our understanding of conditions in which anabolism is altered (e.g., exercise, feeding, growth, debilitating and metabolic pathologies).
骨骼肌蛋白质合成通常通过使用标记氨基酸（例如 [13C]亮氨酸或 [13C]、[15N]、[2H]苯丙氨酸）作为示踪剂的前体-产物标记方法来确定。尽管这种方法可靠地用于确定蛋白质合成率，但该方法需要在受控环境中进行实验，因此限制了我们对长时间内（即综合/累积评估）自由生活条件下肌肉蛋白质更新的理解。另一种示踪剂 2H2O 已成功用于测量小鼠、大鼠、鱼类和人类的肌肉蛋白质合成率。此外，这些测量包括喂养和运动等干扰因素，而没有排除常见的环境和生物学因素。在这篇综述中，我们讨论了使用 2H2O 测量肌肉蛋白质合成的原理，并强调了最近检查喂养和运动影响的研究。本文提供的框架应有助于肌肉生物学家设计实验，以加深我们对合成代谢改变的条件的理解（例如运动、喂养、生长、虚弱和代谢病理）。
