Fitzgerald E M, Djamgoz M B
Department of Biology, Imperial College of Science, Technology and Medicine, London, UK.
J Neurosci Methods. 1995 Jul;59(2):273-7. doi: 10.1016/0165-0270(94)00213-z.
The sensitivies of double-barrelled K(+)-selective micro-electrodes (KSMs) employing the low-impedance membrane cocktail based on the neutral K(+)-selective ion carrier valinomycin (Fluka, Cocktail B 60398) to the following 3 different classes of inhibitors of K+ transport were measured: (1) general metabolic inhibitors (dinitrophenol, potassium cyanide, sodium azide, rotenone, dicyclohexylcarbodiimide, salicylhydroxamic acid); (2) P-type ATPase inhibitors (vanadate, ouabain, amiloride, SCH 28080); and (3) anion-dependent K+ transport inhibitors (bumetanide, 4-acetamide-4-isothiocyanostilbene-2,2-disulphonic acid). Of the 12 inhibitors tested, only dinitrophenol had any significant effect on the response of KSMs to K+ activity. Comparison of the calibrations in solutions with and without 0.1 mM dinitrophenol showed that this inhibitor behaved as a 'classical' interferent whereby its contribution to the K+ activity signal was statistically significant at K+ activities of 36.0 mM and less. However, at higher K+ activities (97.0 mM), dinitrophenol interference was not significant. It was possible to correct for the DNP interference and to obtain measurements of intracellular K+ activity in insect muscles.
使用基于中性钾（K⁺）选择性离子载体缬氨霉素（Fluka，鸡尾酒B 60398）的低阻抗膜鸡尾酒的双管钾（K⁺）选择性微电极（KSM），对以下3种不同类型的K⁺转运抑制剂的敏感性进行了测量：（1）一般代谢抑制剂（二硝基苯酚、氰化钾、叠氮化钠、鱼藤酮、二环己基碳二亚胺、水杨羟肟酸）；（2）P型ATP酶抑制剂（钒酸盐、哇巴因、阿米洛利、SCH 28080）；以及（3）阴离子依赖性K⁺转运抑制剂（布美他尼、4-乙酰胺-4-异硫氰基芪-2,2-二磺酸）。在测试的12种抑制剂中，只有二硝基苯酚对KSM对K⁺活性的响应有任何显著影响。在含有和不含0.1 mM二硝基苯酚的溶液中进行校准的比较表明，这种抑制剂表现为一种“经典”干扰物，即在K⁺活性为36.0 mM及以下时，其对K⁺活性信号的贡献具有统计学意义。然而，在较高的K⁺活性（97.0 mM）下，二硝基苯酚的干扰并不显著。可以校正二硝基苯酚的干扰，并获得昆虫肌肉细胞内K⁺活性的测量值。
