Referenced in: none

Automatically associated channels: SK2

Title: T-type Ca2+ channels, SK2 channels and SERCAs gate sleep-related oscillations in thalamic dendrites.

Authors: Lucius Cueni, Marco Canepari, Rafael Lujan, Yann Emmenegger, Masahiko Watanabe, Chris T Bond, Paul Franken, John P Adelman, Anita Lüthi

Journal, date & volume: Nat. Neurosci., 2008 Jun , 11, 683-92

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/18488023

Abstract
T-type Ca2+ channels (T channels) underlie rhythmic burst discharges during neuronal oscillations that are typical during sleep. However, the Ca2+-dependent effectors that are selectively regulated by T currents remain unknown. We found that, in dendrites of nucleus reticularis thalami (nRt), intracellular Ca2+ concentration increases were dominated by Ca2+ influx through T channels and shaped rhythmic bursting via competition between Ca2+-dependent small-conductance (SK)-type K+ channels and Ca2+ uptake pumps. Oscillatory bursting was initiated via selective activation of dendritically located SK2 channels, whereas Ca2+ sequestration by sarco/endoplasmic reticulum Ca2+-ATPases (SERCAs) and cumulative T channel inactivation dampened oscillations. Sk2-/- (also known as Kcnn2) mice lacked cellular oscillations, showed a greater than threefold reduction in low-frequency rhythms in the electroencephalogram of non-rapid-eye-movement sleep and had disrupted sleep. Thus, the interplay of T channels, SK2 channels and SERCAs in nRt dendrites comprises a specialized Ca2+ signaling triad to regulate oscillatory dynamics related to sleep.