Preoptic area sleep-regulating mechanisms.
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.
Szymusiak
R
R
Research Service (151A3), V.A. Greater Los Angeles Healthcare System, Departments of Medicine and Psychology, University of California, Los Angeles, USA.
Steininger
T
T
Alam
N
N
McGinty
D
D
D000200:Action Potentials / Q000502:physiology; D000818:Animals; D007025:Anterior Hypothalamic Nucleus / Q000166:cytology / Q000502:physiology; D020532:Basal Nucleus of Meynert / Q000166:cytology / Q000502:physiology; D001933:Brain Stem / Q000166:cytology / Q000502:physiology; D006801:Humans; D009474:Neurons / Q000166:cytology / Q000502:physiology*; D011301:Preoptic Area / Q000166:cytology / Q000502:physiology*; D012890:Sleep / Q000502:physiology*