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PubMed · 11256189

Preoptic area sleep-regulating mechanisms.

R Szymusiak·T Steininger·N Alam·D McGinty
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Abstract

Evidence is summarized for the existence of a sleep-regulating mechanism within the preoptic area of the hypothalamus, including the results of lesion, stimulation, and neuronal recording studies. Recent findings employing the c-fos protein immunohistochemical method, have localized putative sleep-regulatory neurons to the ventrolateral preoptic area (vlPOA) and the median preoptic nucleus (MnPn). Electrophysiological studies have confirmed the presence of neurons with sleep-related discharge in the vlPOA. Neurons in the vlPOA that exhibit c-fos protein immunoreactivity during sleep contain the inhibitory neuromodulators galanin and gamma-aminobutyric acid (GABA). These neurons also project to monoaminergic arousal systems, particularly the histaminergic cell groups in the posterior hypothalamus. POA neurons can be hypothesized to provide sleep-related inhibitory control over multiple arousal systems in the forebrain and brainstem.

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Action PotentialsAnimalsAnterior Hypothalamic NucleusBasal Nucleus of MeynertBrain StemHumansNeuronsPreoptic AreaSleepJournal ArticleReview

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R Szymusiak, T Steininger, N Alam, D McGinty. 2001. Preoptic area sleep-regulating mechanisms.. https://pubmed.ncbi.nlm.nih.gov/11256189/

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