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TWIK-1 contributes to the intrinsic excitability of dentate granule cells in mouse hippocampus
- Source :
- Molecular Brain, MOLECULAR BRAIN(7)
- Publication Year :
- 2014
- Publisher :
- BioMed Central, 2014.
-
Abstract
- Background Two-pore domain K+ (K2P) channels have been shown to modulate neuronal excitability. However, physiological function of TWIK-1, the first identified member of the mammalian K2P channel family, in neuronal cells is largely unknown. Results We found that TWIK-1 proteins were expressed and localized mainly in the soma and proximal dendrites of dentate gyrus granule cells (DGGCs) rather than in distal dendrites or mossy fibers. Gene silencing demonstrates that the outwardly rectifying K+ current density was reduced in TWIK-1-deficient granule cells. TWIK-1 deficiency caused a depolarizing shift in the resting membrane potential (RMP) of DGGCs and enhanced their firing rate in response to depolarizing current injections. Through perforant path stimulation, TWIK-1-deficient granule cells showed altered signal input-output properties with larger EPSP amplitude values and increased spiking compared to control DGGCs. In addition, supra-maximal perforant path stimulation evoked a graded burst discharge in 44% of TWIK-1-deficient cells, which implies impairment of EPSP-spike coupling. Conclusions These results showed that TWIK-1 is functionally expressed in DGGCs and contributes to the intrinsic excitability of these cells. The TWIK-1 channel is involved in establishing the RMP of DGGCs; it attenuates sub-threshold depolarization of the cells during neuronal activity, and contributes to EPSP-spike coupling in perforant path-to-granule cell synaptic transmission. Electronic supplementary material The online version of this article (doi:10.1186/s13041-014-0080-z) contains supplementary material, which is available to authorized users.
- Subjects :
- Male
K2P channel
Dentate gyrus granule cell
Potassium Channels
TWIK-1
Action Potentials
Intrinsic excitability
Cellular and Molecular Neuroscience
Potassium Channels, Tandem Pore Domain
Medicine
Animals
Molecular Biology
K2p channel
Mouse Hippocampus
Physiological function
business.industry
Dentate gyrus
Granule (cell biology)
Excitatory Postsynaptic Potentials
Potassium channel
Mice, Inbred C57BL
Gene Knockdown Techniques
Dentate Gyrus
Synapses
Excitatory postsynaptic potential
Psychopharmacology
business
Neuroscience
Research Article
Subjects
Details
- Language :
- English
- ISSN :
- 17566606
- Volume :
- 7
- Database :
- OpenAIRE
- Journal :
- Molecular Brain
- Accession number :
- edsair.doi.dedup.....f04e850243ab32e95124b8e59597f459