Changes in Na+-K+-ATPase activity influence cell attachment to fibronectin
Changes in Na+-K+-ATPase activity influence cell attachment to fibronectin
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DOI：
10.1152/ajpcell.00117.2001
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发表时间：
2002-02-01
影响因子：
5.5
通讯作者：
Aperia, A
中科院分区：
文献类型：
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作者：
Belusa, R;Aizman, O;Aperia, A
大多数重要的细胞功能依赖于细胞内离子稳态的精细调节。在这里，我们已经证明，使用未转染或转染野生型大鼠抗瓦巴因Na+-K+-ATPase的COS细胞，Na+-K+-ATPase的部分抑制对细胞与纤维连接蛋白的附着有显著影响。在未转染的细胞和表达野生型Na+-K+-ATPase的细胞中，瓦巴因剂量依赖性地降低了附着，但在表达瓦巴因不敏感的Na+-K+-ATPase的细胞中没有降低附着，而通过降低细胞外K+浓度抑制Na+-K+-ATPase可以降低所有三种细胞类型的附着。30%的Na+-K+- atp酶抑制显著减弱附着。Na+-K+- atp酶抑制引起细胞内Ca2+浓度的持续增加，掩盖了未处理细胞在附着期间观察到的Ca2+瞬态。Ca2+转运体抑制剂显著降低附着，而Na+/H+交换体抑制剂则没有。瓦巴因降低了黏附激酶的自磷酸化，但对细胞表面整合素的表达没有影响。这些结果表明，Na+-K+- atp酶活性水平强烈影响细胞附着，可能是通过对细胞内Ca2+的影响。
Most vital cellular functions are dependent on a fine-tuned regulation of intracellular ion homeostasis. Here we have demonstrated, using COS cells that were untransfected or transfected with wild-type rat ouabain-resistant Na+-K+-ATPase, that partial inhibition of Na+-K+-ATPase has a dramatic influence on cell attachment to fibronectin. Ouabain dose-dependently decreased attachment in untransfected cells and in cells expressing wild-type Na+-K+-ATPase, but not in cells expressing ouabain-insensitive Na+-K+-ATPase, whereas inhibition of Na+-K+-ATPase by lowering extracellular K+ concentration decreased attachment in all three cell types. Thirty percent inhibition of Na+-K+-ATPase significantly attenuated attachment. Na+-K+-ATPase inhibition caused a sustained increase in the intracellular Ca2+ concentration that obscured Ca2+ transients observed in untreated cells during attachment. Inhibitors of Ca2+ transporters significantly decreased attachment, but inhibition of Na+/H+ exchanger did not. Ouabain reduced focal adhesion kinase autophosphorylation but had no effect on cell surface integrin expression. These results suggest that the level of Na+-K+-ATPase activity strongly influences cell attachment, possibly by an effect on intracellular Ca2+.