Schell R E, Tran N V, Bramhall J S
Department of Oral and Maxillofacial Surgery, Harbor UCLA General Hospital, Torrance 90509.
Biochem Biophys Res Commun. 1989 Mar 31;159(3):1165-70. doi: 10.1016/0006-291x(89)92232-8.
As part of an investigation into the nephrotoxic effects of the polyene antibiotic Amphotericin B we have studied its effects on the ion permeability of purified renal brush border membrane vesicles. Membrane potentials were measured using a potential sensitive carbocyanine dye, and ion permeabilities were calculated from the constant field equation. Amphotericin B significantly altered the ionic permeability sequence of isolated membranes and caused a selectivity for increasing the permeation of anions. Permeability changes induced by 2.0 micrograms/ml Amphotericin B resulted in an estimated hyperpolarization of the membrane from -50 mV to -72 mV. In addition, the kinetic parameters of Na+ dependent transport of organic metabolites were examined. The maximum change in fluorescence was decreased significantly in the presence of Amphotericin B. These results suggest that the ionic state of the renal cell membrane is significantly altered by the presence of Amphotericin B.
作为对多烯抗生素两性霉素B肾毒性作用研究的一部分，我们研究了其对纯化的肾刷状缘膜囊泡离子通透性的影响。使用电位敏感的羰花青染料测量膜电位，并根据恒定场方程计算离子通透性。两性霉素B显著改变了分离膜的离子通透性顺序，并导致对增加阴离子通透的选择性。2.0微克/毫升两性霉素B诱导的通透性变化导致膜电位估计从-50毫伏超极化到-72毫伏。此外，还研究了有机代谢物的Na+依赖性转运的动力学参数。在两性霉素B存在下，荧光的最大变化显著降低。这些结果表明，两性霉素B的存在显著改变了肾细胞膜的离子状态。
