Korzeniewski Bernard, Deschodt-Arsac Véronique, Calmettes Guillaume, Franconi Jean-Michel, Diolez Philippe
Résonance Magnétique des Systèmes Biologiques, UMR5536 Centre National de la Recherche Scientifique, Université Victor Segalen Bordeaux 2, France.
Biochem J. 2008 Jul 15;413(2):343-7. doi: 10.1042/BJ20080162.
During low-to-high work transition in adult mammalian heart in vivo the concentrations of free ADP, ATP, PCr (phosphocreatine), P(i) and NADH are essentially constant, in striking contrast with skeletal muscle. The direct activation by calcium ions of ATP usage and feedback activation of ATP production by ADP (and P(i)) alone cannot explain this perfect homoeostasis. A comparison of the response to adrenaline (increase in rate-pressure product and [PCr]) of the intact beating perfused rat heart with the elasticities of the PCr producer and consumer to PCr concentration demonstrated that both the ATP/PCr-producing block and ATP/PCr-consuming block are directly activated to a similar extent during physiological heart activation. Our finding constitutes a direct evidence for the parallel-activation mechanism of the regulation of oxidative phosphorylation in heart postulated previously in a theoretical way.
在成年哺乳动物心脏从低工作状态向高工作状态转变的过程中，体内游离ADP、ATP、磷酸肌酸（PCr）、无机磷酸（P(i)）和NADH的浓度基本保持恒定，这与骨骼肌形成了鲜明对比。仅靠钙离子对ATP利用的直接激活以及ADP（和P(i)）对ATP生成的反馈激活无法解释这种完美的稳态。将完整跳动的灌注大鼠心脏对肾上腺素的反应（心率 - 血压乘积和[PCr]增加）与PCr产生者和消耗者对PCr浓度的弹性进行比较，结果表明，在生理性心脏激活过程中，ATP/PCr产生模块和ATP/PCr消耗模块被直接激活的程度相似。我们的发现为先前从理论上推测的心脏氧化磷酸化调节的平行激活机制提供了直接证据。
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