A simple model of aerobic metabolism: applications to work transitions in muscle.
A simple model of aerobic metabolism: applications to work transitions in muscle.
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有氧代谢的简单模型：在肌肉工作转换中的应用。
DOI：
10.1152/ajpcell.1990.258.6.c995
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发表时间：
1990
期刊：
影响因子：
--
通讯作者：
Connett,RJ
中科院分区：
文献类型：
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作者：
Funk,CI;ClarkJr,A;Connett,RJ
将动力学添加到磷酸盐能量系统模型中 [Connett。是。 J.生理学。 254 (Regulatory Integrative Comp. Physiol. 23): R949-R959, 1988]，我们提供了一个分析肌肉组织代谢瞬态的框架。我们修改了早期模型的形式并引入了缓冲因子，该因子可测量磷酸肌酸对腺嘌呤核苷酸的缓冲。磷酸盐能量状态的时间过程可以根据以下条件计算：1) 腺苷三磷酸酶 (ATPase) 速率，2) pH 值，以及 3) 线粒体驱动功能，即以磷酸盐能量状态表示的 ATP 产量。我们使用稳态测量得出的线粒体驱动功能来预测休息-工作转换的时间进程。对大鼠腓肠肌转变的预测与公布的值一致。该模型用于测试不同的现有耗氧量 (VO2) 调节假设。每个假设都会产生特定的线粒体驱动功能，进而在转变过程中产生特定的磷酸盐能量状态时间过程。基于以 ADP 作为底物的酶动力学的线粒体驱动功能导致时间进程与数据不匹配。与磷酸肌酸、Pi、磷酸化电位或高能磷酸键池（磷酸盐势能）呈线性关系的线粒体驱动函数与数据具有良好的一致性。
Adding kinetics to the model of the phosphate energy system [Connett. Am. J. Physiol. 254 (Regulatory Integrative Comp. Physiol. 23): R949-R959, 1988], we provide a framework for analyzing metabolic transients in muscle tissue. We modify the formalism of the earlier model and introduce a buffering factor, which measures buffering of adenine nucleotides by phosphocreatine. The time course of the phosphate energy state can be calculated given the following: 1) adenosinetriphosphatase (ATPase) rate, 2) pH, and 3) a mitochondrial driving function, i.e., ATP production in terms of the phosphate energy state. We use mitochondrial driving functions derived from steady-state measurements to predict the time courses for rest-work transitions. Predictions for transitions in the rat gastrocnemius muscle agree with published values. The model is used to test different existing hypotheses of oxygen consumption (VO2) regulation. Each hypothesis generates a specific mitochondrial driving function, which in turn generates a specific time course of phosphate energy state during transitions. A mitochondrial driving function based on enzyme kinetics with ADP as a substrate leads to time courses not matching the data. Mitochondrial driving functions that are linear with phosphocreatine, Pi, phosphorylation potential, or the pool of high-energy phosphate bonds (phosphate potential energy) gave good agreement with the data.