镧对艾氏腹水癌细胞电泳迁移率和被动阳离子转运的影响。

The effect of lanthanum on electrophoretic mobility and passive cation movements of the Ehrlich ascites tumor cell.

作者信息

Smith T C

出版信息

J Cell Physiol. 1976 Jan;87(1):47-52. doi: 10.1002/jcp.1040870107.

Abstract

We have investigated the effects of La+3 binding to the surface of Ehrlich ascites tumor cells on cell electrophoretic mobility and passive movements of Na+ and K+. Incubation of tumor cells in La+3-containing media results in a La+3 concentration-dependent decrease in net surface charge negativity. At [La+3] greater than 0.5 mM, the net surface charge becomes positive with maximum positivity occurring at [La+3] = 0.9 mM. The effects of La+3 binding on passive Na+ and K+ movements were investigated by following 22Na and K+ losses from ouabain-inhibited cells. Neither low (0.02) nor high (1.0 mM) [La+3] had any effect on the K+ efflux rate coefficient. 22Na losses from control and La+3-treated cells were consistent with washouts from two cellular compartments. Low [La+3] (0.02 mM) was without effect on Na+ losses from the cells. However, higher [La+3] (1.0 mM) resulted in a 48% inhibition of Na+ loss from the more slowly exchanging compartment. These results are not consistent with simple electrostatic interactions exerting a major influence on the passive movements of Na+ and K+. It is suggested that La+3 interacts with sites specific for Na+, perhaps involved in a carrier-mediated exchange system.

摘要

我们研究了La³⁺与艾氏腹水瘤细胞表面结合对细胞电泳迁移率以及Na⁺和K⁺被动转运的影响。将肿瘤细胞置于含La³⁺的培养基中孵育，会导致净表面电荷负值呈La³⁺浓度依赖性降低。当[La³⁺]大于0.5 mM时，净表面电荷变为正值，在[La³⁺]=0.9 mM时出现最大正值。通过追踪哇巴因抑制的细胞中²²Na和K⁺的流失，研究了La³⁺结合对Na⁺和K⁺被动转运的影响。低浓度（0.02 mM）和高浓度（1.0 mM）的[La³⁺]对K⁺外流速率系数均无任何影响。对照细胞和经La³⁺处理的细胞中²²Na的流失与从两个细胞区室的洗脱情况一致。低浓度[La³⁺]（0.02 mM）对细胞中Na⁺的流失没有影响。然而，较高浓度[La³⁺]（1.0 mM）导致从交换较慢的区室中Na⁺流失受到48%的抑制。这些结果与简单的静电相互作用对Na⁺和K⁺的被动转运产生主要影响不一致。有人提出La³⁺与Na⁺特异性位点相互作用，可能参与了载体介导的交换系统。