Changes in the composition of brain interstitial ions control the sleep-wake cycle.
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ABSTRACT:
SUBMITTER: Ding F
PROVIDER: S-EPMC5441687 | biostudies-literature | 2016 Apr
REPOSITORIES: biostudies-literature
Publications
Changes in the composition of brain interstitial ions control the sleep-wake cycle.
Ding Fengfei F O'Donnell John J Xu Qiwu Q Kang Ning N Goldman Nanna N Nedergaard Maiken M
Science (New York, N.Y.) 20160401 6285
Wakefulness is driven by the widespread release of neuromodulators by the ascending arousal system. Yet, it is unclear how these substances orchestrate state-dependent, global changes in neuronal activity. Here, we show that neuromodulators induce increases in the extracellular K(+) concentration ([K(+)]e) in cortical slices electrically silenced by tetrodotoxin. In vivo, arousal was linked to AMPA receptor-independent elevations of [K(+)]e concomitant with decreases in [Ca(2+)]e, [Mg(2+)]e, [H( ...[more]
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