Responses of extrahypothalamic neurons to short temperature transients during the ultradian wake-sleep cycle

AbstractDeep brain stimulation (DBS) is currently a standard procedure for advanced Parkinson’s disease. Many centers employ awake physiological navigation and stimulation assessment to optimize DBS localization and outcome. To enable DBS under sedation, asleep DBS, we characterized the cortico-basal ganglia neuronal network of two nonhuman primates under propofol, ketamine, and interleaved propofol-ketamine (IPK) sedation. Further, we compared these sedation states in the healthy and Parkinsonian condition to those of healthy sleep. Ketamine increases high-frequency power and synchronization while propofol increases low-frequency power and synchronization in polysomnography and neuronal activity recordings. Thus, ketamine does not mask the low-frequency oscillations used for physiological navigation toward the basal ganglia DBS targets. The brain spectral state under ketamine and propofol mimicked rapid eye movement (REM) and Non-REM (NREM) sleep activity, respectively, and the IPK protocol resembles the NREM-REM sleep cycle. These promising results are a meaningful step toward asleep DBS with nondistorted physiological navigation.

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Melatonin in Wine and Beer: Beneficial Effects

Molecules ◽

10.3390/molecules26020343 ◽

2021 ◽

Vol 26 (2) ◽

pp. 343

Author(s):

Javier Marhuenda ◽

Débora Villaño ◽

Raúl Arcusa ◽

Pilar Zafrilla

Keyword(s):

Intracellular Signaling ◽

Plasma Concentrations ◽

Radical Scavenging ◽

Direct Interaction ◽

Melatonin Receptors ◽

Current Evidence ◽

Sleep Cycle ◽

Beneficial Effects ◽

Neuroprotective Actions ◽

Radical Scavenging Properties

Melatonin is a hormone secreted in the pineal gland with several functions, especially regulation of circadian sleep cycle and the biological processes related to it. This review evaluates the bioavailability of melatonin and resulting metabolites, the presence of melatonin in wine and beer and factors that influence it, and finally the different benefits related to treatment with melatonin. When administered orally, melatonin is mainly absorbed in the rectum and the ileum; it has a half-life of about 0.45–1 h and is extensively inactivated in the liver by phase 2 enzymes. Melatonin (MEL) concentration varies from picograms to ng/mL in fermented beverages such as wine and beer, depending on the fermentation process. These low quantities, within a dietary intake, are enough to reach significant plasma concentrations of melatonin, and are thus able to exert beneficial effects. Melatonin has demonstrated antioxidant, anticarcinogenic, immunomodulatory and neuroprotective actions. These benefits are related to its free radical scavenging properties as well and the direct interaction with melatonin receptors, which are involved in complex intracellular signaling pathways, including inhibition of angiogenesis and cell proliferation, among others. In the present review, the current evidence on the effects of melatonin on different pathophysiological conditions is also discussed.

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Effects of subacute doses of psychotropic drugs on the sleep cycle in the Cat: Attempt to use a data processing system

Pharmacological Research Communications ◽

10.1016/s0031-6989(80)80095-6 ◽

1980 ◽

Vol 12 (4) ◽

pp. 379-383 ◽

Cited By ~ 2

Author(s):

A. Diena ◽

F. Allocca

Keyword(s):

Data Processing ◽

Psychotropic Drugs ◽

Processing System ◽

Sleep Cycle ◽

Data Processing System

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Fundamental Dynamical Modes Underlying Human Brain Synchronization

Computational and Mathematical Methods in Medicine ◽

10.1155/2012/912729 ◽

2012 ◽

Vol 2012 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Catalina Alvarado-Rojas ◽

Michel Le Van Quyen

Keyword(s):

Large Scale ◽

Brain Regions ◽

Electrode Placement ◽

High Dimensional ◽

Sleep Cycle ◽

Epileptic Patients ◽

Brain States ◽

Intracranial Recordings ◽

Characteristic Dynamic

Little is known about the long-term dynamics of widely interacting cortical and subcortical networks during the wake-sleep cycle. Using large-scale intracranial recordings of epileptic patients during seizure-free periods, we investigated local- and long-range synchronization between multiple brain regions over several days. For such high-dimensional data, summary information is required for understanding and modelling the underlying dynamics. Here, we suggest that a compact yet useful representation is given by a state space based on the first principal components. Using this representation, we report, with a remarkable similarity across the patients with different locations of electrode placement, that the seemingly complex patterns of brain synchrony during the wake-sleep cycle can be represented by a small number of characteristic dynamic modes. In this space, transitions between behavioral states occur through specific trajectories from one mode to another. These findings suggest that, at a coarse level of temporal resolution, the different brain states are correlated with several dominant synchrony patterns which are successively activated across wake-sleep states.

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Increased Cerebrovascular Sensitivity to Endothelin-1 in a Rat Model of Obstructive Sleep Apnea: A Role for Endothelin Receptor B

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.2014.214 ◽

2015 ◽

Vol 35 (3) ◽

pp. 402-411 ◽

Cited By ~ 15

Author(s):

David J Durgan ◽

Randy F Crossland ◽

Eric E Lloyd ◽

Sharon C Phillips ◽

Robert M Bryan

Keyword(s):

Obstructive Sleep Apnea ◽

Sleep Apnea ◽

Transient Receptor Potential ◽

Cerebral Arteries ◽

Receptor Potential ◽

Fold Increase ◽

Sleep Cycle ◽

Rock Inhibitor ◽

Endothelin 1 ◽

Obstructive Sleep

Obstructive sleep apnea (OSA) is associated with cerebrovascular diseases. However, little is known regarding the effects of OSA on the cerebrovascular wall. We tested the hypothesis that OSA augments endothelin-1 (ET-1) constrictions of cerebral arteries. Repeated apneas (30 or 60 per hour) were produced in rats during the sleep cycle (8 hours) by remotely inflating a balloon implanted in the trachea. Four weeks of apneas produced a 23-fold increase in ET-1 sensitivity in isolated and pressurized posterior cerebral arteries (PCAs) compared with PCAs from sham-operated rats (EC50=10−9.2 mol/L versus 10−10.6 mol/L; P<0.001). This increased sensitivity was abolished by the ET-B receptor antagonist, BQ-788. Constrictions to the ET-B receptor agonist, IRL-1620, were greater in PCAs from rats after 2 or 4 weeks of apneas compared with that from sham-operated rats ( P=0.013). Increased IRL-1620 constrictions in PCAs from OSA rats were normalized with the transient receptor potential channel (TRPC) blocker, SKF96365, or the Rho kinase (ROCK) inhibitor, Y27632. These data show that OSA increases the sensitivity of PCAs to ET-1 through enhanced ET-B activity, and enhanced activity of TRPCs and ROCK. We conclude that enhanced ET-1 signaling is part of a pathologic mechanism associated with adverse cerebrovascular outcomes of OSA.

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