Youmans S J, Barry C R
Department of Medicine, East Carolina University School of Medicine, Greenville, NC 27858-4354.
Biochem Biophys Res Commun. 1989 May 30;161(1):312-9. doi: 10.1016/0006-291x(89)91598-2.
We investigated the inhibitory effects of 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl) on ATP-dependent H+ accumulation by membrane vesicles prepared from the turtle urinary bladder epithelium. NBD-Cl at 30 microM was found to completely inhibit the vanadate-insensitive component of H+ transport, with half-maximal inhibition occurring at 4.2 to 5.4 microM. In contrast, the vanadate-inhibitable component was unaffected by 30 microM NBD-Cl. At high concentrations (300 microM), both components were fully inhibited. The results confirm the presence of two distinct H+ transport processes in turtle bladder membranes and identify selective inhibitors, NBD-Cl and vanadate, for each process.
我们研究了7-氯-4-硝基苯并-2-恶唑-1,3-二氮杂茂（NBD-Cl）对由龟膀胱上皮制备的膜囊泡中ATP依赖性H⁺积累的抑制作用。发现30微摩尔的NBD-Cl可完全抑制H⁺转运的钒酸盐不敏感成分，半数最大抑制浓度在4.2至5.4微摩尔之间。相比之下，钒酸盐可抑制的成分不受30微摩尔NBD-Cl的影响。在高浓度（300微摩尔）时，两种成分均被完全抑制。这些结果证实了龟膀胱膜中存在两种不同的H⁺转运过程，并确定了每种过程的选择性抑制剂NBD-Cl和钒酸盐。
