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Extracellular divalent ions modulate TREK-2-like channel conductance in prefrontal pyramidal neurons in rats
, 1, 2
Affiliations- Centre for Preclinical Research and Technology (CePT), Medical University of Warsaw,, Banacha 1b, 02-097 Warszawa, Poland
- Warsaw University of Life Science, Department of Biophysics, Nowoursynowska 159, build. 34, 02-776 Warsaw, Poland
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Abstract
Background: The aim of the study was to investigate, with the use of the patch clamp technique, the dependence of the conductance of the TREK-2-like potassium leak channel in the medial prefrontal cortex
pyramidal neurons on the presence of extracellular magnesium and calcium ions. It is suspected that
TREK-2 channels regulate mood and may be associated with the pathophysiology of depression. Since
magnesium and calcium deficiency contribute to depressive symptoms, we investigated how TREK-2- like
channel pore propertie change in the absence of divalent cations.
Results: Single-channel currents were recorded in a cell-attached configuration in enzymatically dispersed
pyramidal neurons of the prefrontal cortex in rats. Spontaneous TREK-2-like channel activity was recorded
either in the presence or absence of magnesium and calcium ions in extracellular solution. A significant
increase in the inward channel conductance was observed when divalent cations were removed from
the extracellular solution. Inward rectification was also increased when the bath temperature was raised
to 34-37°C.
Conclusions: The study confirmed that the activity of TREK-2-like channels is affected by the presence of
magnesium and calcium ions in the extracellular solution. Therefore, in vivo, the TREK-2-like channel may
possibly participate in the prefrontal cortex dysfunction associated with the deficiency of divalent cations.
Abstract
Background: The aim of the study was to investigate, with the use of the patch clamp technique, the dependence of the conductance of the TREK-2-like potassium leak channel in the medial prefrontal cortex
pyramidal neurons on the presence of extracellular magnesium and calcium ions. It is suspected that
TREK-2 channels regulate mood and may be associated with the pathophysiology of depression. Since
magnesium and calcium deficiency contribute to depressive symptoms, we investigated how TREK-2- like
channel pore propertie change in the absence of divalent cations.
Results: Single-channel currents were recorded in a cell-attached configuration in enzymatically dispersed
pyramidal neurons of the prefrontal cortex in rats. Spontaneous TREK-2-like channel activity was recorded
either in the presence or absence of magnesium and calcium ions in extracellular solution. A significant
increase in the inward channel conductance was observed when divalent cations were removed from
the extracellular solution. Inward rectification was also increased when the bath temperature was raised
to 34-37°C.
Conclusions: The study confirmed that the activity of TREK-2-like channels is affected by the presence of
magnesium and calcium ions in the extracellular solution. Therefore, in vivo, the TREK-2-like channel may
possibly participate in the prefrontal cortex dysfunction associated with the deficiency of divalent cations.
Keywords
magnesium and calcium homeostasis; depression; TREK-2 channels; leak potassium channels; patch-clamp
About this articleTitle
Extracellular divalent ions modulate TREK-2-like channel conductance in prefrontal pyramidal neurons in rats
Journal
Issue
Article type
Original article
Pages
31-34
Published online
2019-02-08
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895
Article views/downloads
811
DOI
Bibliographic record
Medical Research Journal 2019;4(1):31-34.
Keywords
magnesium and calcium homeostasis
depression
TREK-2 channels
leak potassium channels
patch-clamp
Authors
Ewa Nurowska
Milena Adamiec
Beata Dworakowska
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