N-methyl-D-aspartate receptors mediate activity-dependent down-regulation of potassium channel genes during the expression of homeostatic intrinsic plasticity.

Autor: Lee KY; Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, 407 South Goodwin Avenue, 524 Burrill Hall, Urbana, IL, 61801, USA. lky@life.illinois.edu., Royston SE; Program in Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, Illinois, 61801, USA. sroysto2@illinois.edu.; Medical Scholars Program, University of Illinois at Urbana-Champaign, Urbana, Illinois, 61801, USA. sroysto2@illinois.edu., Vest MO; Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, 407 South Goodwin Avenue, 524 Burrill Hall, Urbana, IL, 61801, USA. vest2@illinois.edu., Ley DJ; Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, 407 South Goodwin Avenue, 524 Burrill Hall, Urbana, IL, 61801, USA. ley.danielj@gmail.com., Lee S; Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, 407 South Goodwin Avenue, 524 Burrill Hall, Urbana, IL, 61801, USA. lee852@illinois.edu., Bolton EC; Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, 407 South Goodwin Avenue, 524 Burrill Hall, Urbana, IL, 61801, USA. boltonec@life.illinois.edu., Chung HJ; Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, 407 South Goodwin Avenue, 524 Burrill Hall, Urbana, IL, 61801, USA. chunghj@life.illinois.edu.; Program in Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, Illinois, 61801, USA. chunghj@life.illinois.edu.
Jazyk: angličtina
Zdroj: Molecular brain [Mol Brain] 2015 Jan 20; Vol. 8, pp. 4. Date of Electronic Publication: 2015 Jan 20.
DOI: 10.1186/s13041-015-0094-1
Abstrakt: Background: Homeostatic intrinsic plasticity encompasses the mechanisms by which neurons stabilize their excitability in response to prolonged and destabilizing changes in global activity. However, the milieu of molecular players responsible for these regulatory mechanisms is largely unknown.
Results: Using whole-cell patch clamp recording and unbiased gene expression profiling in rat dissociated hippocampal neurons cultured at high density, we demonstrate here that chronic activity blockade induced by the sodium channel blocker tetrodotoxin leads to a homeostatic increase in action potential firing and down-regulation of potassium channel genes. In addition, chronic activity blockade reduces total potassium current, as well as protein expression and current of voltage-gated Kv1 and Kv7 potassium channels, which are critical regulators of action potential firing. Importantly, inhibition of N-Methyl-D-Aspartate receptors alone mimics the effects of tetrodotoxin, including the elevation in firing frequency and reduction of potassium channel gene expression and current driven by activity blockade, whereas inhibition of L-type voltage-gated calcium channels has no effect.
Conclusions: Collectively, our data suggest that homeostatic intrinsic plasticity induced by chronic activity blockade is accomplished in part by decreased calcium influx through N-Methyl-D-Aspartate receptors and subsequent transcriptional down-regulation of potassium channel genes.
Databáze: MEDLINE
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