Cook J S, Vaughan G L, Proctor W R, Brake E T
J Cell Physiol. 1975 Aug;86(1):59-70. doi: 10.1002/jcp.1040860108.
The alkali cation content of HeLa cells is independent of culture density and of whether the cells are grown in suspension or attached to the culture vessel. With a cell doubling time of 28 hours, the cell K content turns over approximately once per hour. Following partial blockade of the alkali-cation transport system with ouabain, two distinct but interrelated mechanisms operate in the cellular response: (a) an increase in intracellular Na stimulates the pump so that the short-term alteration in electrolyte compostition is less than would be expected from the fraction of pump sites inhibited, and (b) there is a cycloheximide-sensitive recovery in transport capacity reflecting a restoration of functional transport sites to their normal density on the cell surface. Experimental manipulations that mimic the effect of ouabain lead to a stimulation of transport, but they do not result in an increase in the number of ouabain-binding sites on the surface. The data are consistent with a four-to-six hour turn-over of transport sites at the surface, but there is no evidence for a speicific induction of the transport system within this short-term recovery period.
HeLa细胞中的碱金属阳离子含量与培养密度无关，也与细胞是悬浮生长还是贴壁生长在培养容器上无关。细胞倍增时间为28小时，细胞内钾含量大约每小时更新一次。在用哇巴因部分阻断碱金属阳离子转运系统后，细胞反应中有两种不同但相互关联的机制在起作用：(a) 细胞内钠的增加刺激了泵，因此电解质组成的短期变化小于根据被抑制的泵位点比例所预期的变化；(b) 转运能力有对放线菌酮敏感的恢复，这反映了功能性转运位点在细胞表面恢复到其正常密度。模拟哇巴因作用的实验操作会导致转运的刺激，但不会导致表面哇巴因结合位点数量的增加。数据与表面转运位点四到六小时的更新一致，但没有证据表明在这个短期恢复期内转运系统有特异性诱导。
