Cl− channels in basolateral renal medullary memnbranes: III. Determinants of single-channel activity
- 1 December 1990
- journal article
- research article
- Published by Springer Nature in The Journal of Membrane Biology
- Vol. 118 (3), 269-278
- https://doi.org/10.1007/bf01868611
Abstract
We evaluated the effects of vawrying aqueous Cl− concentrations, and of the arginyl- and lysyl-specific reagent phenylglyoxal (PGO), on the properties of Cl− channels fused from basolaterally enriched renal medullary vesicles into planar lipid bilayers. The major channel properties studied were the anion selectivity sequence, anionic requirements for, channel activity. and the efects of varying Cl− concentrations and/or PGO on the relation between holding voltageV H -mV) and open-time probability (P o). Reducingcis Cl− concentrations, in the range 50–320mm, produced a linear reduction in fractional open time (P v) with a half-maximal reduction inP o atcis Cl−≈170mM. Channel activity was sustained by equimolar replacement ofcis Cl− with F−, but not with impermeant isethionate. Fortrans solutions, the relation between Cl− concentration andP 0 at 10mm Cl−. Reducingcis Cl− had no effect on the gating charge (Z) for channel opening, but altered significantly the voltage-independent, energy (δG) for channel opening. Phenylglyoxal (PGO) reducedZ and altered δG for Cl− channel activity when added tocis, but nottrans solutions, Furthermore, in the presence ofcis PGO, reducing thecis Cl− concentration had no effect onZ but altered δG. Thus we propose thatcis PGO and,cis Cl− concentrations affect separate sites determining channel activity at the extracellular faces of, these Cl− channels.This publication has 16 references indexed in Scilit:
- Cl− transport in basolateral renal medullary vesicles: I. Cl− transport in intact vesiclesThe Journal of Membrane Biology, 1990
- Cl− transport in basolateral renal medullary vesicles: II. Cl− channels in planar lipid bilayersThe Journal of Membrane Biology, 1990
- Activation of K+ channels in renal medullary vesicles by cAMP-dependent protein kinaseThe Journal of Membrane Biology, 1989
- Characterization of chloride channels in membrane vesicles from the kidney outer medullaThe Journal of Membrane Biology, 1989
- Structure and Function of Voltage-Sensitive Ion ChannelsScience, 1988
- An anion channel of sarcoplasmic reticulum incorporated into planar lipid bilayers: Single-channel behavior and conductance propertiesThe Journal of Membrane Biology, 1987
- Blockage of chloride channels by HEPES bufferProceedings of the Royal Society of London. B. Biological Sciences, 1987
- Effects of antidiuretic hormone on cellular conductive pathways in mouse medullary thick ascending limbs of Henle: II. Determinants of the ADH-mediated increases in transepithelial voltage and in net Cl− absorptionThe Journal of Membrane Biology, 1984
- Chloride activity in cells of isolated perfused cortical thick ascending limbs of rabbit kidneyPflügers Archiv - European Journal of Physiology, 1983
- Reconstitution of Excitable Cell Membrane Structure in VitroCirculation, 1962