Intracellular modulation of acid secretion in rat inner medullary collecting duct cells.
Intracellular modulation of acid secretion in rat inner medullary collecting duct cells.
复制标题
大鼠内髓集合管细胞酸分泌的细胞内调节。
DOI：
10.1152/ajprenal.1994.266.1.f94
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
Alexander,EA
中科院分区：
文献类型：
--
作者：
Schwartz,JH;Masino,SA;Nichols,RD;Alexander,EA
在这项研究中，我们确定了一些重要的因素，在酸化过程中的大鼠内髓集合管（IMCD）细胞的培养。在细胞酸化之后，即，细胞pH（pHi）= 6.51 +/- 0.02，pHi增加0.046 +/- 0.003单位/分钟。N-乙基马来酰亚胺、N，N ′-环己基碳二亚胺和巴弗洛霉素使该速率降低超过85%。与此相反，奥美拉唑和Sch-28080没有影响。1，2-双（2-氨基苯氧基）乙烷-N，N，N，N '-四乙酸可阻止细胞内Ca 2+浓度（[Ca 2 +]i）的升高，使pHi恢复速率降至0.013 +/- 0.002单位/min。钙调蛋白抑制剂或细胞松弛素B和秋水仙素破坏细胞骨架元素也显著降低pHi恢复。此外，这些细胞含有酸性囊泡，并经历pH调节的内吞作用和胞吐作用，其通过破坏细胞骨架而被抑制。我们的结论是，在我们培养的大鼠IMCD细胞系，质子分泌介导的H（+）-腺苷三磷酸酶。pHi的变化通过信号级联产生酸分泌的改变，所述信号级联需要[Ca 2 +]i的变化、钙调蛋白的激活、完整的细胞骨架以及胞吐和胞吞速率的改变。
In this study we defined some of the important elements in the acidification process of rat inner medullary collecting duct (IMCD) cells in culture. After cell acidification, i.e., cell pH (pHi) = 6.51 +/- 0.02, pHi increased 0.046 +/- 0.003 units/min. N-ethylmaleimide, N,N'-cyclohexylcarbodiimide, and bafilomycin reduced this rate by over 85%. In contrast, omeprazole and Sch-28080 had no effect. 1,2-Bis(2-aminophenoxy)ethane-N,N,N,N'-tetraacetic acid, which prevents a rise in cell Ca2+concentration ([Ca2+]i) reduced the rate of pHi recovery to 0.013 +/- 0.002 units/min. Calmodulin inhibitors or disruption of cytoskeletal elements with cytochalasin B and colchicine also reduced pHi recovery significantly. In addition, these cells contain acidic vesicles and undergo pHi-regulated endocytosis and exocytosis, which are inhibited by disrupting the cytoskeleton. We conclude that, in our cultured line of rat IMCD cells, proton secretion is mediated by an H(+)-adenosinetriphosphatase. Changes in pHi produce alterations in acid secretion through a signal cascade that requires changes in [Ca2+]i, activation of calmodulin, an intact cytoskeleton, and alteration in the rate of exocytosis and endocytosis.