Volume regulation of murine T lymphocytes relies on voltage-dependent and two-pore domain potassium channels

ABSTRACT Severe malnutrition in children is frequently associated with infectious diseases. Animal models have been useful for studying the effects of malnutrition. One of the immunosuppressive mechanisms of malnutrition is inhibition of the activation of T lymphocytes. The voltage-dependent K(V) potassium channels are vital for the activation of T lymphocytes. The blockade of K(V) channels inhibits the activation of T lymphocytes. Malnutrition could affect the suitable synthesis of K(V) channels in T lymphocytes, producing changes in the magnitude and/or dependency of the voltage of the K+ current. We reported a significant decrease in the K+ current and activation to a 20 mV more positive membrane potential in T lymphocytes of rats with severe malnutrition. These results indicate that the diminution in the K+ conductance by alteration of K(V) channels in severe malnutrition is one of the mechanisms that inhibit the activation of T lymphocytes.

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Faculty Opinions recommendation of Voltage-dependent gating of KCNH potassium channels lacking a covalent link between voltage-sensing and pore domains.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.725409273.793508121 ◽

2015 ◽

Author(s):

Jamie Vandenberg ◽

Matthew Perry

Keyword(s):

Potassium Channels ◽

Voltage Sensing ◽

Voltage Dependent ◽

Pore Domains

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Interaction between tetraethylammonium and amino acid residues in the pore of cloned voltage-dependent potassium channels.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(20)89487-3 ◽

1991 ◽

Vol 266 (12) ◽

pp. 7583-7587

Author(s):

M P Kavanaugh ◽

M D Varnum ◽

P B Osborne ◽

M J Christie ◽

A E Busch ◽

...

Keyword(s):

Amino Acid ◽

Potassium Channels ◽

Amino Acid Residues ◽

Voltage Dependent

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Differential expression of two-pore domain potassium channels in rat cerebellar granule neurons

Biochemical and Biophysical Research Communications ◽

10.1016/j.bbrc.2014.10.012 ◽

2014 ◽

Vol 453 (4) ◽

pp. 754-760 ◽

Cited By ~ 7

Author(s):

Paulina Burgos ◽

Rafael Zúñiga ◽

Pedro Domínguez ◽

Fernando Delgado-López ◽

Leigh D. Plant ◽

...

Keyword(s):

Potassium Channels ◽

Differential Expression ◽

Cerebellar Granule Neurons ◽

Granule Neurons ◽

Cerebellar Granule ◽

Pore Domain

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Activation-inactivation of potassium channels and development of the potassium-channel spike in internally perfused squid giant axons.

The Journal of General Physiology ◽

10.1085/jgp.78.1.43 ◽

1981 ◽

Vol 78 (1) ◽

pp. 43-61 ◽

Cited By ~ 17

Author(s):

I Inoue

Keyword(s):

Potassium Channels ◽

Potassium Channel ◽

Voltage Clamp ◽

Time Constant ◽

Equilibrium Potential ◽

Giant Axons ◽

Dependent Inactivation ◽

Voltage Dependent ◽

Time Courses ◽

Calcium Permeability

A spike that is the result of calcium permeability through potassium channels was separated from the action potential is squid giant axons internally perfused with a 30 mM NaF solution and bathed in a 100 mM CaCl2 solution by blocking sodium channels with tetrodotoxin. Currents through potassium channels were studied under voltage clamp. The records showed a clear voltage-dependent inactivation of the currents. The inactivation was composed of at least two components; one relatively fast, having a time constant of 20--30 ms, and the other very slow, having a time constant of 5--10 s. Voltage clamp was carried out with a variety of salt compositions in both the internal and external solutions. A similar voltage-dependent inactivation, also composed of the two components, was recognized in all the current through potassium channels. Although the direction and intensity of current strongly depended on the salt composition of the solutions, the time-courses of these currents at corresponding voltages were very similar. These results strongly suggest that the inactivation of the currents in attributable to an essential, dynamic property of potassium channels themselves. Thus, the generation of a potassium-channel spike can be understood as an event that occurs when the equilibrium potential across the potassium channel becomes positive.

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