Na+/H+ antiporter of brush border vesicles: studies with acridine orange uptake.
Na+/H+ antiporter of brush border vesicles: studies with acridine orange uptake.
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刷状缘囊泡的 Na /H 逆向转运蛋白：吖啶橙吸收的研究。
DOI：
10.1152/ajprenal.1982.242.6.f733
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发表时间：
1982
期刊：
影响因子：
--
通讯作者：
Yee,VJ
中科院分区：
文献类型：
--
作者：
Warnock,DG;Reenstra,WW;Yee,VJ
用吖啶橙子荧光猝灭法研究了兔肾皮质刷状缘膜囊泡Na+/H+逆向转运蛋白对pH梯度的影响。当吖啶橙子（一种弱碱）被吸收到酸性囊内空间时，观察到淬灭。Na+/H+交换与Na+摄取和流出研究。吖啶橙子荧光猝灭证明了Na+/H+反向转运蛋白的阳离子特异性（即，钠和锂），并被阿米洛利抑制。用K+/H+反向转运蛋白尼日利亚菌素进行的平行研究表明，吖啶橙子对pH梯度的反应非常迅速。因此，吖啶橙子平衡在我们的Na+/H+逆向转运蛋白的研究中不是速率限制。进行初始速率测量以获得Na+/H+反向转运蛋白的动力学参数。在钠内流研究中，吖啶橙子荧光变化的半最大速率是在外部钠浓度为13.3 +/- 0.5 mM时获得的。
Fluorescence quenching of acridine orange was used to characterize the generation and collapse of pH gradients by the Na+/H+ antiporter of brush border membrane vesicles prepared from rabbit renal cortex. Quenching was observed when acridine orange, a weak base, was taken up to an acidic intravesicular space. Na+/H+ exchange was examined with both Na+ uptake and efflux studies. Acridine orange fluorescence quenching demonstrated the cation specificity of the Na+/H+ antiporter (i.e., sodium and lithium) and was inhibited by amiloride. Parallel studies with nigericin, a K+/H+ antiporter, demonstrated that acridine orange responded very rapidly to pH gradients. Therefore, acridine orange equilibration was not rate limiting in our studies of the Na+/H+ antiporter. Initial rate measurements were made to obtain kinetic parameters for the Na+/H+ antiporter. In sodium influx studies, the half-maximal rate of acridine orange fluorescence change was obtained with an external sodium concentration of 13.3 +/- 0.5 mM.