Noack E, Greeff K
Recent Adv Stud Cardiac Struct Metab. 1975;5:165-70.
With rising concentrations of KCl the rate of Ca2+ uptake was moderately increased by 37 percent. NaCl induced a strong decrease of the rate of Ca2+ uptake from 498 to 194 nmoles of Ca2+ per sec-gm of protein (0-100 mM NAaCl). Elevating the K+/Na+ quotient from 0.1 to 15.7, we found a concomitant alteration of the rate of Ca2+ uptake which is mediated exclusively by sodium ions. These data indicate that with lowering of the K+/Na+ gradient there is a marked diminution of the mitochondrial rate of Ca2+ uptake and Ca storage. Our findings may contribute to answering how Na+-K+ exchange at the cell membrane may influence intracellular Ca2+ binding and Ca2+ turnover.
随着氯化钾浓度的升高，钙离子摄取速率适度增加了37%。氯化钠导致钙离子摄取速率大幅下降，从每秒每克蛋白质498纳摩尔钙离子降至194纳摩尔钙离子（0 - 100毫摩尔氯化钠）。将钾离子/钠离子比值从0.1提高到15.7时，我们发现钙离子摄取速率随之发生改变，且这种改变完全由钠离子介导。这些数据表明，随着钾离子/钠离子梯度降低，线粒体的钙离子摄取和储存速率显著降低。我们的研究结果可能有助于回答细胞膜上的钠钾交换如何影响细胞内钙离子结合和钙离子周转。
