POTASSIUM AND SODIUM MOVEMENTS IN THE EHRLICH MOUSE ASCITES TUMOR CELL
POTASSIUM AND SODIUM MOVEMENTS IN THE EHRLICH MOUSE ASCITES TUMOR CELL
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DOI：
10.1085/jgp.41.3.565
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发表时间：
1958-01-01
影响因子：
3.8
通讯作者：
HEMPLING, HG
中科院分区：
文献类型：
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作者：
HEMPLING, HG
已经对钠和钾进出埃利希腹水肿瘤细胞的运动进行了研究。在22[度]C的稳态条件下，在没有外源葡萄糖的情况下，钾和钠的细胞通量平均为0.8 [mu]M/107细胞/小时。或3.0 pM/cm。电池可以积累钾，挤出钠，对抗两种离子的电化学梯度。在所报道的实验条件下，分离这两种离子的输运系统是可能的。因此，在低温条件下，代谢减少，两种离子的净通量是不同的。此外，在2[度]C下24小时后，外源性葡萄糖源使钾的积累增加7倍，而钠的挤压不受葡萄糖存在的影响。同样，钾的交换速率与温度有关，辅酶Q10值高达5，而钠的交换速率对温度不敏感，辅酶Q10值为1.2至1.6。糖酵解作为运输过程的能量来源已经被消除，因为这些过程在缺乏外源葡萄糖的情况下进行。据估计，从葡萄糖的总氧化代谢中获得的能量中，最多需要0.3%的能量来支持钾和钠的独立运输。
Studies have been conducted on the movements of sodium and potassium into and out of the Ehrlich ascites tumor cell. Under steady state conditions, at 22[degree]C, in the absence of an exogenous source of glucose, the cell flux for both potassium and sodium averaged 0.8 [mu]M/107 cells/hr. or 3.0 pM/cm.2/ sec. The cell can accumulate potassium and extrude sodium against electrochemical gradients for both ions. It is possible under the experimental conditions reported to separate the transport systems for these two ions. Thus, it has been shown that under conditions of low temperature with a diminished metabolism, net fluxes for the two ions are different. Also, following periods of 24 hours at 2[degree]C, an exogenous source of glucose enhances the accumulation of potassium sevenfold while sodium extrusion is uninfluenced by the presence of glucose. Similarly potassium exchange rates are temperature-dependent, with Q10 values as high as 5, while exchange rates for sodium are temperature-insensitive, with Q10 values of 1.2 to 1.6. Glycolysis has been eliminated as an energy source for the transport processes since these processes go on in the absence of an exogenous source of glucose. It is estimated that a maximum of 0.3 per cent of the energy derived from the total oxidative metabolism of glucose would be required to support independent transport of potassium and sodium.