Jacobus W E
Biochem Biophys Res Commun. 1985 Dec 31;133(3):1035-41. doi: 10.1016/0006-291x(85)91240-9.
Flux rates for phosphate metabolites were calculated using the equation for radial diffusion, assuming heart intracellular conditions and a 5% concentration gradient. The data show that while the flux of phosphocreatine is about 3 times faster than ATP, both are more than two orders of magnitude greater than the known maximum rate of ATP utilization. In contrast, since the concentration of free ADP is very low, its flux is below the maximum rate of ATP turnover, while the flux of creatine is almost 3 orders of magnitude greater than ADP. The data suggest that the rate of high-energy phosphate production could be limited by ADP diffusion, with creatine thus substituting as the primary cytoplasmic-mitochondrial phosphate acceptor.
在假定心肌细胞内环境及5%浓度梯度的情况下，使用径向扩散方程计算了磷酸代谢物的通量率。数据显示，虽然磷酸肌酸的通量比ATP快约3倍，但两者均比已知的ATP最大利用速率大两个数量级以上。相比之下，由于游离ADP的浓度非常低，其通量低于ATP周转的最大速率，而肌酸的通量几乎比ADP大3个数量级。数据表明，高能磷酸生成速率可能受ADP扩散限制，因此肌酸可作为主要的细胞质-线粒体磷酸受体。
