Regulation of VO2 in red muscle: do current biochemical hypotheses fit in vivo data?
Regulation of VO2 in red muscle: do current biochemical hypotheses fit in vivo data?
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红肌摄氧量的调节：当前的生化假设是否符合体内数据？
DOI：
10.1152/ajpregu.1989.256.4.r898
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
Honig,CR
中科院分区：
文献类型：
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作者：
Connett,RJ;Honig,CR
用于测试通过胞质磷酸盐能量状态调节O2消耗（VO 2）的生化模型的观察结果必须包括细胞内pH值的变化和/或腺嘌呤核苷酸或磷酸盐库的变化[Connett，R.代谢控制的分析：使用缩放肌酸激酶模型的新见解。Am. J.Physiol.254（Regulatory Integrative Comp.Physiol.23）：R949-R959，1988]。数据收集了广泛的能量周转犬肌肉原位。细胞内PO 2，糖酵解中间体，腺嘌呤核苷酸，肌酸，磷酸肌酸（PCr），磷酸盐，和细胞内的pH值进行了测定，为每个肌肉。PO 2用于消除VO 2可能受到O2限制（PO 2小于0.5 Torr）的肌肉。这消除了异质性的一个重要来源。由于腺嘌呤核苷酸和磷酸盐池相对于肌酸池是恒定的，因此模型之间的区分仅取决于pH值。观察到的pH值范围为7.2至5.9，无法将[PCr]与log[（ATP 4-]/[ADP 3-][H2 PO 4-]）（磷酸化电位）分离，作为VO 2的调节参数。然而，[ADP]作为一个独立的监管机构可能会被取消。由于90%的VO 2的变异性占磷酸盐能量学，一个独立的氧化还原组分必须是小的，当细胞内PO 2大于0.5托。
Observations used to test biochemical models of the regulation of O2 consumption (VO2) by cytosolic phosphate energy state must include a change in intracellular pH and/or a change in the adenine nucleotide or phosphate pools [Connett, R. J. Analysis of metabolic control: new insights using a scaled creatine kinase model. Am. J. Physiol. 254 (Regulatory Integrative Comp. Physiol. 23): R949-R959, 1988]. Data were collected over a wide range of energy turnover from canine muscles in situ. Intracellular PO2, glycolytic intermediates, adenine nucleotides, creatine, phosphocreatine (PCr), phosphate, and intracellular pH were determined for each muscle. PO2 was used to eliminate muscles in which VO2 could have been O2 limited (PO2 less than 0.5 Torr). This removed an important source of heterogeneity. Because adenine nucleotide and phosphate pools were constant relative to the creatine pool, discrimination among models depended solely on pH. The observed pH range from 7.2 to 5.9 did not permit separation of [PCr] from log[( ATP4-]/[ADP3-][H2PO4-]) (phosphorylation potential) as a regulatory parameter for VO2. However, [ADP] could be eliminated as an independent regulator. Because 90% of variability in VO2 was accounted for by phosphate energetics, an independent redox component must be small when intracellular PO2 greater than 0.5 Torr.