Benos D J
Am J Physiol. 1982 Mar;242(3):C131-45. doi: 10.1152/ajpcell.1982.242.3.C131.
The potassium-sparing diuretic amiloride has proven to be a useful pharmacological tool for elucidating the molecular basis and physiological regulation of facilitated sodium entry in tissues and cells. There are two general classes of Na+ transport mechanisms which are sensitive to this drug: 1) a conductive Na+ entry pathway found in electrically high resistance epithelia and 2) a Na+-H+ electroneutral exchange system found in certain leaky epithelia such as the renal proximal tubule. This latter system is also found in many different cellular preparations and seems to function in cell proliferation and differentiation, volume regulation, and intracellular pH regulation. In these cells, this exchange pathway becomes operational usually after some external stimuli. Much higher concentrations of amiloride are required to inhibit the exchange pathway than those required to inhibit the Na+ entry pathway. This drug is the most potent and specific inhibitor of Na+ entry found to date and thus affords the opportunity to be used as a label for the isolation of these transport moieties.
保钾利尿剂阿米洛利已被证明是一种有用的药理学工具，可用于阐明组织和细胞中钠易化转运的分子基础和生理调节机制。对这种药物敏感的钠转运机制一般有两类：1）在电高阻上皮中发现的一种传导性钠进入途径；2）在某些渗漏上皮（如近端肾小管）中发现的一种钠-氢电中性交换系统。后一种系统在许多不同的细胞制剂中也有发现，似乎在细胞增殖和分化、体积调节以及细胞内pH调节中发挥作用。在这些细胞中，这种交换途径通常在受到一些外部刺激后开始起作用。抑制交换途径所需的阿米洛利浓度比抑制钠进入途径所需的浓度高得多。这种药物是迄今为止发现的最有效、最特异的钠进入抑制剂，因此有机会用作分离这些转运部分的标记物。
