Beauge L A, Sjodin R A, Ortiz O
Biochim Biophys Acta. 1975 Apr 21;389(1):189-93. doi: 10.1016/0005-2736(75)90396-x.
The membrane potential (Em) of sartorius muscle fibers was made insensitive to [K+] by equilibration in a 95 mM K+, 120 mM Na+ Ringer solution. Under these conditions a potassium-activated, ouabain-sensitive sodium efflux was observed which had characteristics similar to those seen in muscles with Em sensitive to [K+]. In addition, in the presence of 10 mM K+, these muscles were able to produce a net sodium extrusion against an electrochemical gradient which was also inhibited by 10- minus 4 M oubain. This suggests that the membrane potential does not play a major role in the potassium activation of the sodium pump in muscles.
通过在含95 mM钾、120 mM钠的任氏溶液中平衡，使缝匠肌纤维的膜电位（Em）对[K+]不敏感。在这些条件下，观察到一种钾激活、哇巴因敏感的钠外流，其特征与膜电位对[K+]敏感的肌肉中所见的相似。此外，在10 mM钾存在的情况下，这些肌肉能够逆着电化学梯度产生净钠外流，且这种外流也受到10^-4 M哇巴因的抑制。这表明膜电位在肌肉钠泵的钾激活过程中并不起主要作用。
