Ba2+‐sensitive K+ channels in luminal‐membrane vesicles from pars convoluta of rabbit proximal tubule

FEBS Letters

Jacobsen, Christian¹  Røigaard-Petersen, Hans¹  Sheikh, M.I.¹ 

[1] Institute of Medical Biochemistry, University of Aarhus, DK-8000 Aarhus C, Denmark

关键词: K+ channel;    Ba2+ sensitivity;    Membrane vesicle;    (Pars convoluta);   

DOI  :  10.1016/0014-5793(89)80124-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

This paper describes properties of ⁸⁶Rb⁺ fluxes through a novel K⁺ channel in luminal-membrane vesicles isolated from pars convoluta of rabbit proximal tubule. The uptake of ⁸⁶Rb⁺ into potassium salt loaded vesicles was specifically inhibited by Ba²⁺. The isotope accumulation is driven by an electrical diffusion potential as shown in experiments using these membrane vesicles loaded with anions of different membrane permeability and was as follows: gluconate > SO²⁻ ₄ > Cl⁻. Furthermore, the vesicles containing the channels show a cation selectivity with the order K⁺ > Rb⁺ > Li⁺ > Na⁺ = choline⁺.

【 授权许可】

Unknown