Huang K C, Dinno M A, Gelbart D R
Proc Soc Exp Biol Med. 1976 Apr;151(4):779-84. doi: 10.3181/00379727-151-39306.
The jejunal mucosal membrane of albino mice was used to study the electrical properties and ion transport. The membrane was bathed in Krebs-Ringer solution with or without glucose. When ethacrynic acid (EA), furosemide, or amiloride was added to the bathing fluid of both sides, a transient increase followed by a decrease of both potential difference (PD) and short circuit current (Isc) were observed. In glucose-containing bathing medium, EA inhibited both net Na and Cl flux and residual flux; however, EA had little effect on both Na and Cl flux in glucose-free bathing medium. Studies using everted intestinal sac technique showed that EA inhibited both glucose and L-tyrosine across the mucosal membrane against concentration gradients. Furosemide and amiloride were less potent than EA in inhibiting the Na and Cl flux when the bathing solution contained glucose. But these two compounds had no effect on glucose and L-tyrosine transport across the intestinal mucosa. Furthermore, they did inhibit Cl flux even in the condition of glucose-free bathing medium. It is postulated that all three diuretics act on the brush-border membrane of the intestine. EA probably inhibits the Na-glucose cotransporting system; furosemide and amiloride inhibit the simple diffusion process of Na entry of Cl exit by decreasing the conductance of the membrane.
采用白化小鼠的空肠黏膜来研究其电特性和离子转运。将黏膜置于含有或不含葡萄糖的 Krebs-Ringer 溶液中。当在两侧的浴液中加入依他尼酸（EA）、呋塞米或阿米洛利时，观察到电位差（PD）和短路电流（Isc）先短暂升高，随后降低。在含葡萄糖的浴液介质中，EA 抑制净 Na 和 Cl 通量以及残余通量；然而，在无葡萄糖的浴液介质中，EA 对 Na 和 Cl 通量几乎没有影响。采用外翻肠囊技术的研究表明，EA 抑制葡萄糖和 L-酪氨酸逆浓度梯度跨黏膜转运。当浴液含有葡萄糖时，呋塞米和阿米洛利在抑制 Na 和 Cl 通量方面的效力低于 EA。但这两种化合物对葡萄糖和 L-酪氨酸跨肠黏膜的转运没有影响。此外，即使在无葡萄糖的浴液介质条件下，它们也能抑制 Cl 通量。据推测，这三种利尿剂均作用于肠道的刷状缘膜。EA 可能抑制 Na-葡萄糖共转运系统；呋塞米和阿米洛利通过降低膜电导来抑制 Na 进入和 Cl 流出的简单扩散过程。
