Studies on terminal differentiation of rat renal proximal tubular cells in culture: ouabain-sensitive K and Na transport.
Studies on terminal differentiation of rat renal proximal tubular cells in culture: ouabain-sensitive K and Na transport.
复制标题
培养中大鼠肾近端肾小管细胞终末分化的研究：哇巴因敏感的 K 和 Na 转运。
DOI：
10.1111/j.1748-1716.1988.tb08309.x
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发表时间：
1988
期刊：
影响因子：
--
通讯作者：
Lechene,C
中科院分区：
文献类型：
--
作者：
Larsson,SH;Aperia,A;Lechene,C
我们使用电子探针分析研究了大鼠近端肾小管细胞中Na‐K ATP酶介导的Na和K转运的个体发生。从10日龄幼龄（Y）和40日龄成年（A）大鼠的肾脏中培养细胞。在实验之前，通过在无K培养基中孵育将细胞加载Na并去除K。通过将细胞从无K培养基转移到含有5 mM K的培养基中，重新激活Na-K泵后，测量哇巴因敏感性Na和K转运的最大速率。在培养2天的细胞中，哇巴因敏感的Na和K净初始转运率在A细胞中显著高于Y细胞。在培养的2至4天之间，Y和A细胞中哇巴因敏感的Na和K转运速率显著降低。培养2 ~ 4天，Y细胞K/Na比值显著降低，而A细胞K/Na比值未显著降低。K/Na比值的降低是由于Na含量的显著增加。在无钾培养基中孵育后，在培养4天的A和Y细胞中观察到细胞内溶质净积累，但在培养2天的A和Y细胞中未观察到。这种增加可以在培养2天的细胞中测量。随着培养时间的延长，Na K泵活性降低，A细胞和Y细胞之间的差异不可测量。我们之前曾观察到，在A细胞培养2至4天后，钠和钾的净渗透率会降低，但在Y细胞中则不然。在培养4天的Y细胞中，泵活性的降低而不改变Na和K渗透性导致细胞内Na含量的增加。
We have studied the ontogeny of Na‐K ATPase‐mediated Na and K transport in rat renal proximal tubular cells using electron probe analysis. The cells were cultured from kidneys of 10‐day‐old, young (Y), and 40‐day‐old, adult (A) rats. Before an experiment cells were Na‐loaded and K‐dcpleted by incubation in K‐free medium. The maximum rate of ouabain‐sensitive Na and K transport was measured after reactivating the Na‐K pump by transferring the cells from K‐free medium to medium containing 5 mM K. In cells cultured for 2 days, ouabain‐sensitive Na and K net initial transport rates were significantly higher in A than in Y cells. Between 2 and 4 days in culture there was a significant decrease in ouabain‐sensitive Na and K transport rates in both Y and A cells. From 2 to 4 days of culture there was, in Y but not in A cells, a significant decrease in K/Na ratio. The decrease in K/Na ratio was due to a significant increase in Na content. After incubation in K‐free medium, net intracellular solute accumulation was observed in A and Y cells cultured for 4 days but not in A and Y cells cultured for 2 days.In conclusion, maximal Na‐ and K‐pump‐mediated transport increases during terminal differentiation. This increase can be measured in cells cultured for 2 days. With longer time in culture, Na K pump activity decreases and the difference between A and Y cells is not measurable. We had previously observed that net Na and K permeabilities decrease from 2 to 4 days in culture in A but not in Y cells. In Y cells cultured for 4 days, a decrease in pump activity without a change in Na and K permeability causes an increase in intracellular Na content.