Voltage activation and hysteresis of the non-selective voltage-dependent channel in the intact human red cell
Autor: | Berit I. Kristensen, Lars R. Jensen, Poul Bennekou, Palle Christophersen, Trine L. Barksmann |
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Rok vydání: | 2003 |
Předmět: |
Erythrocytes
Patch-Clamp Techniques Sodium Biophysics Analytical chemistry chemistry.chemical_element Calcium-Transporting ATPases Chloride Ion Channels Membrane Potentials Potassium Channels Calcium-Activated Electrochemistry medicine Humans Patch clamp Physical and Theoretical Chemistry Ion channel Membrane potential Voltage-dependent calcium channel Chemistry General Medicine Potassium channel Electrophysiology Calcium Channels medicine.drug |
Zdroj: | Bioelectrochemistry (Amsterdam, Netherlands). 62(2) |
ISSN: | 1567-5394 |
Popis: | Suspension of intact human red cells in media with low chloride and sodium concentrations (isotonic sucrose substitution) results in strongly inside positive membrane potentials, which activate the voltage-dependent non-selective cation (NSVDC) channel. By systematic variation of the initial Nernst potentials for chloride (degree of ion substitution) as well as the chloride conductance (block by NS1652), and by exploiting the interplay between the Ca(2+)-permeable NSVDC channel, the Ca(2+)-activated K+ channel (the Gardos channel) and the Ca(2+)-pump, a graded activation of the NSVDC channel was achieved. Under these conditions, it was shown that the NSVDC channels exist in two states of activation depending on the initial conditions for the activation. The hysteretic behaviour, which in patch clamp experiments has been found for the individual channel unit, is thus retained at the cellular level and can be demonstrated with red cells in suspension. |
Databáze: | OpenAIRE |
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