Discrepancy in stoichiometry of steady-state muscle [Pi] and [PCr] induced by exercise.
Discrepancy in stoichiometry of steady-state muscle [Pi] and [PCr] induced by exercise.
复制标题
运动引起的稳态肌肉 [Pi] 和 [PCr] 的化学计量差异。
DOI：
10.1152/jappl.1987.63.5.2053
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发表时间：
1987
期刊：
影响因子：
--
通讯作者：
Coulson,RL
中科院分区：
文献类型：
--
作者：
Caton,JR;Mole,PA;Coulson,RL
磷核磁共振用于量化6名成年男性前臂肌肉在1.0至3.5 W的工作速率范围内代谢磷酸盐、细胞内pH和工作速率之间的关系。在四次训练（1.0、2.0和3.0或1.5、2.5和3.5 W）中，每一次都研究了三种工作速率，并在每次训练之前和期间进行了测量，从而允许通过回归分析划分可归因于休息、工作依赖和时间依赖代谢功能的方差。在两次运动之间的休息时间内，[ATP]或细胞内[H+]均无时间依赖性变化。相比之下，总核磁共振(NMR)-可见磷池（TVPP）随着时间的推移而降低，磷酸肌酸（PCr）和无机磷酸盐（Pi）对TVPP的降低有显著贡献。肌肉[ATP]在所有强度下都没有变化。细胞内[H+]与工作速率成比例适度增加。[PCr]的减少和[Pi]的增加与工作速率成正比，PCr消耗的工作依赖系数大约是Pi产量的1.5倍。Pi线宽度和运动伪影都不能解释TVPP的下降，因此运动中Pi积累的减少可能代表了它在一些核磁共振不可见的肌肉池中被隔离和/或损失到血液中。无论过程如何，它与工作速率成正比，并在运动后持续至少10-15分钟。
Phosphorus nuclear magnetic resonance was used to quantify the relations between metabolic phosphates, intracellular pH, and work rate in forearm muscle of six adult men over a range of work rates from 1.0 to 3.5 W. Three work rates were studied in each of four sessions (either 1.0, 2.0, and 3.0 or 1.5, 2.5, and 3.5 W), with measurements made before and during each bout, thereby permitting the partition of the variance attributable to rest, work-dependent, and time-dependent metabolic functions by regression analysis. There were no time-dependent changes in either [ATP] or intracellular [H+] as assessed during the rest intervals between bouts of exercise. In contrast, the total nuclear magnetic resonance (NMR)-visible phosphorus pool (TVPP) decreased with time, with both phosphocreatine (PCr) and inorganic phosphate (Pi) contributing significantly to TVPP reduction. Muscle [ATP] was unchanged by work at all intensities. Intracellular [H+] increased moderately and proportionately to work rate. [PCr] decreased and [Pi] increased in proportion to work rate, with the work-dependent coefficient for PCr consumption approximately 1.5 times that of Pi production. Neither Pi line width nor motion artifact accounted for the decrease in TVPP, so the reduced Pi accumulation in exercise may represent its sequestering in some NMR-invisible muscle pool and/or loss to the blood. Whatever the process involved, it is proportional to work rate and persists for at least 10–15 min after exercise.