59250
doi
10.1002/glia.23040
oai:zenodo.org:59250
user-inmind
user-eu
Strobaek, Dorte
Saniona A/S, Baltorpvej 154, 2750, Ballerup, Denmark
Hougaard, Charlotte
Saniona A/S, Baltorpvej 154, 2750, Ballerup, Denmark
Klein, Jessica
Saniona A/S, Baltorpvej 154, 2750, Ballerup, Denmark
Pinborg, Lars H
Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark and Epilepsy Clinic, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
Mikkelsen, Jens D
Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
Christophersen, Palle
Saniona A/S, Baltorpvej 154, 2750, Ballerup, Denmark
Quantification of the functional expression of the Ca2+ -activated K+ channel KCa 3.1 on microglia from adult human neocortical tissue.
Blomster, Linda V
Saniona A/S, Baltorpvej 154, 2750, Ballerup, Denmark and Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
info:eu-repo/semantics/openAccess
Creative Commons Attribution 4.0 International
https://creativecommons.org/licenses/by/4.0/legalcode
neuroinflammation
potassium channel
patch clamp
glial cell
IK channel
BK channel
<p>The K<sub>Ca</sub> 3.1 channel (KCNN4) is an important modulator of microglia responses in rodents, but no information exists on functional expression on microglia from human adults. We isolated and cultured microglia (max 1% astrocytes, no neurons or oligodendrocytes) from neocortex surgically removed from epilepsy patients and employed electrophysiological whole-cell measurements and selective pharmacological tools to elucidate functional expression of K<sub>Ca</sub> 3.1. The channel expression was demonstrated as a significant increase in the voltage-independent current by NS309, a K<sub>Ca</sub> 3.1/K<sub>Ca</sub> 2 activator, followed by full inhibition upon co-application with NS6180, a highly selective K<sub>Ca</sub> 3.1 inhibitor. A major fraction (79%) of unstimulated human microglia expressed K<sub>Ca</sub> 3.1, and the difference in current between full activation and inhibition (ΔK<sub>Ca</sub> 3.1) was estimated at 292 ± 48 pA at -40 mV (n = 75), which equals at least 585 channels per cell. Serial K<sub>Ca</sub> 3.1 activation/inhibition significantly hyperpolarized/depolarized the membrane potential. The isolated human microglia were potently activated by lipopolysaccharide (LPS) shown as a prominent increase in TNF-α production. However, incubation with LPS neither changed the K<sub>Ca</sub> 3.1 current nor the fraction of K<sub>Ca</sub> 3.1 expressing cells. In contrast, the anti-inflammatory cytokine IL-4 slightly increased the K<sub>Ca</sub> 3.1 current per cell, but as the membrane area also increased, there was no significant change in channel density. A large fraction of the microglia also expressed a voltage-dependent current sensitive to the K<sub>Ca</sub> 1.1 modulators NS1619 and Paxilline and an inward-rectifying current with the characteristics of a K<sub>ir</sub> channel. The high functional expression of K<sub>Ca</sub> 3.1 in microglia from epilepsy patients accentuates the need for further investigations of its role in neuropathological processes.</p>
Zenodo
2016-07-29
info:eu-repo/semantics/article
639164
user-inmind
user-eu
award_title=Imaging of Neuroinflammation in Neurodegenerative Diseases; award_number=278850; award_identifiers_scheme=url; award_identifiers_identifier=https://cordis.europa.eu/projects/278850; funder_id=00k4n6c32; funder_name=European Commission;
1579527128.867083
3542108
md5:2eb5af56b6c7d4ff06af8c570d2191e2
https://zenodo.org/records/59250/files/Blomster_Glia_2016-P28-AM.pdf
public
Glia
64
12
2065-2078
2016-07-29