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Guo R, Wang Y, Yan R, Chen B, Ding W, Gorczyca MT, Ozsoy S, Cai L, Hines RL, Tseng GC, Allocca G, Dong Y, Fang J, Huang YH. Rapid Eye Movement Sleep Engages Melanin-Concentrating Hormone Neurons to Reduce Cocaine Seeking. Biol Psychiatry 2022; 92:880-894. [PMID: 35953320 PMCID: PMC9872495 DOI: 10.1016/j.biopsych.2022.06.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 06/03/2022] [Accepted: 06/06/2022] [Indexed: 01/27/2023]
Abstract
BACKGROUND Persistent sleep disruptions following withdrawal from abused drugs may hold keys to battle drug relapse. It is posited that there may be sleep signatures that predict relapse propensity, identifying which may open new avenues for treating substance use disorders. METHODS We trained male rats (approximately postnatal day 56) to self-administer cocaine. After long-term drug withdrawal (approximately postnatal day 100), we examined the correlations between the intensity of cocaine seeking and key sleep features. To test for causal relationships, we then used behavioral, chemogenetic, or optogenetic methods to selectively increase rapid eye movement sleep (REMS) and measured behavioral and electrophysiological outcomes to probe for cellular and circuit mechanisms underlying REMS-mediated regulation of cocaine seeking. RESULTS A selective set of REMS features was preferentially associated with the intensity of cue-induced cocaine seeking after drug withdrawal. Moreover, selectively increasing REMS time and continuity by environmental warming attenuated a withdrawal time-dependent intensification of cocaine seeking, or incubation of cocaine craving, suggesting that REMS may benefit withdrawal. Warming increased the activity of lateral hypothalamic melanin-concentrating hormone (MCH) neurons selectively during prolonged REMS episodes and counteracted cocaine-induced synaptic accumulation of calcium-permeable AMPA receptors in the nucleus accumbens-a critical substrate for incubation. Finally, the warming effects were partly mimicked by chemogenetic or optogenetic stimulations of MCH neurons during sleep, or intra-accumbens infusions of MCH peptide during the rat's inactive phase. CONCLUSIONS REMS may encode individual vulnerability to relapse, and MCH neuron activities can be selectively targeted during REMS to reduce drug relapse.
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Affiliation(s)
- Rong Guo
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Yao Wang
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Rongzhen Yan
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Bo Chen
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Wanqiao Ding
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Michael T Gorczyca
- Department of Biostatistics, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Sahin Ozsoy
- Somnivore Pty. Ltd., Bacchus Marsh, Victoria, Australia
| | - Li Cai
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Rachel L Hines
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - George C Tseng
- Department of Biostatistics, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Giancarlo Allocca
- Somnivore Pty. Ltd., Bacchus Marsh, Victoria, Australia; Department of Pharmacology and Therapeutics, University of Melbourne, Parkville, Victoria, Australia; Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | - Yan Dong
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania; Department of Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Jidong Fang
- Department of Psychiatry and Behavioral Health, Penn State College of Medicine, Hershey, Pennsylvania
| | - Yanhua H Huang
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania.
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Cocaine-induced neural adaptations in the lateral hypothalamic melanin-concentrating hormone neurons and the role in regulating rapid eye movement sleep after withdrawal. Mol Psychiatry 2021; 26:3152-3168. [PMID: 33093653 PMCID: PMC8060355 DOI: 10.1038/s41380-020-00921-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 09/30/2020] [Accepted: 10/07/2020] [Indexed: 12/21/2022]
Abstract
Sleep abnormalities are often a prominent contributor to withdrawal symptoms following chronic drug use. Notably, rapid eye movement (REM) sleep regulates emotional memory, and persistent REM sleep impairment after cocaine withdrawal negatively impacts relapse-like behaviors in rats. However, it is not understood how cocaine experience may alter REM sleep regulatory machinery, and what may serve to improve REM sleep after withdrawal. Here, we focus on the melanin-concentrating hormone (MCH) neurons in the lateral hypothalamus (LH), which regulate REM sleep initiation and maintenance. Using adult male Sprague-Dawley rats trained to self-administer intravenous cocaine, we did transcriptome profiling of LH MCH neurons after long-term withdrawal using RNA-sequencing, and performed functional assessment using slice electrophysiology. We found that 3 weeks after withdrawal from cocaine, LH MCH neurons exhibit a wide range of gene expression changes tapping into cell membrane signaling, intracellular signaling, and transcriptional regulations. Functionally, they show reduced membrane excitability and decreased glutamatergic receptor activity, consistent with increased expression of voltage-gated potassium channel gene Kcna1 and decreased expression of metabotropic glutamate receptor gene Grm5. Finally, chemogenetic or optogenetic stimulations of LH MCH neural activity increase REM sleep after long-term withdrawal with important differences. Whereas chemogenetic stimulation promotes both wakefulness and REM sleep, optogenetic stimulation of these neurons in sleep selectively promotes REM sleep. In summary, cocaine exposure persistently alters gene expression profiles and electrophysiological properties of LH MCH neurons. Counteracting cocaine-induced hypoactivity of these neurons selectively in sleep enhances REM sleep quality and quantity after long-term withdrawal.
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Vawter MP, Schulmann A, Alhassen L, Alhassen W, Hamzeh AR, Sakr J, Pauluk L, Yoshimura R, Wang X, Dai Q, Sanathara N, Civelli O, Alachkar A. Melanin Concentrating Hormone Signaling Deficits in Schizophrenia: Association With Memory and Social Impairments and Abnormal Sensorimotor Gating. Int J Neuropsychopharmacol 2019; 23:53-65. [PMID: 31563948 PMCID: PMC7442395 DOI: 10.1093/ijnp/pyz051] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 08/30/2019] [Accepted: 09/24/2019] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Evidence from anatomical, pharmacological, and genetic studies supports a role for the neuropeptide melanin concentrating hormone system in modulating emotional and cognitive functions. Genome-wide association studies revealed a potential association between the melanin concentrating hormone receptor (MCHR1) gene locus and schizophrenia, and the largest genome-wide association study conducted to date shows a credible genome-wide association. METHODS We analyzed MCHR1 and pro-melanin concentrating hormone RNA-Seq expression in the prefrontal cortex in schizophrenia patients and healthy controls. Disruptions in the melanin concentrating hormone system were modeled in the mouse brain by germline deletion of MCHR1 and by conditional ablation of melanin concentrating hormone expressing neurons using a Cre-inducible diphtheria toxin system. RESULTS MCHR1 expression is decreased in the prefrontal cortex of schizophrenia samples (false discovery rate (FDR) P < .05, CommonMind and PsychEncode combined datasets, n = 901) while pro-melanin concentrating hormone is below the detection threshold. MCHR1 expression decreased with aging (P = 6.6E-57) in human dorsolateral prefrontal cortex. The deletion of MCHR1 was found to lead to behavioral abnormalities mimicking schizophrenia-like phenotypes: hyperactivity, increased stereotypic and repetitive behavior, social impairment, impaired sensorimotor gating, and disrupted cognitive functions. Conditional ablation of pro-melanin concentrating hormone neurons increased repetitive behavior and produced a deficit in sensorimotor gating. CONCLUSIONS Our study indicates that early disruption of the melanin concentrating hormone system interferes with neurodevelopmental processes, which may contribute to the pathogenesis of schizophrenia. Further neurobiological research on the developmental timing and circuits that are affected by melanin concentrating hormone may lead to a therapeutic target for early prevention of schizophrenia.
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Affiliation(s)
- Marquis P Vawter
- Department of Psychiatry and Human Behavior, School of Medicine, University of California, Irvine, CA,Correspondence: Marquis P. Vawter, PhD, Department of Psychiatry and Human Behavior, School of Medicine, University of California, Irvine, CA 92617 (); and Dr Amal Alachkar, Department of Pharmaceutical Sciences, University of California, Irvine, CA ()
| | - Anton Schulmann
- Department of Psychiatry and Human Behavior, School of Medicine, University of California, Irvine, CA,Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA
| | - Lamees Alhassen
- Department of Psychiatry and Human Behavior, School of Medicine, University of California, Irvine, CA
| | - Wedad Alhassen
- Department of Pharmacology, School of Medicine, University of California, Irvine, CA,Department of Pharmaceutical Sciences, University of California, Irvine, CA
| | - Abdul Rezzak Hamzeh
- John Curtin School of Medical Research, Australian National University, Canberra
| | - Jasmine Sakr
- Department of Pharmaceutical Sciences, University of California, Irvine, CA
| | - Lucas Pauluk
- Department of Pharmacology, School of Medicine, University of California, Irvine, CA
| | - Ryan Yoshimura
- Department of Pharmacology, School of Medicine, University of California, Irvine, CA
| | - Xuejie Wang
- Department of Pharmacology, School of Medicine, University of California, Irvine, CA
| | - Qi Dai
- Department of Pharmacology, School of Medicine, University of California, Irvine, CA
| | - Nayna Sanathara
- Department of Pharmacology, School of Medicine, University of California, Irvine, CA
| | - Olivier Civelli
- Department of Pharmacology, School of Medicine, University of California, Irvine, CA,Department of Pharmaceutical Sciences, University of California, Irvine, CA,Department of Developmental and Cell Biology, School of Medicine, University of California, Irvine, CA
| | - Amal Alachkar
- Department of Pharmaceutical Sciences, University of California, Irvine, CA,Correspondence: Marquis P. Vawter, PhD, Department of Psychiatry and Human Behavior, School of Medicine, University of California, Irvine, CA 92617 (); and Dr Amal Alachkar, Department of Pharmaceutical Sciences, University of California, Irvine, CA ()
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4
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The role of co-neurotransmitters in sleep and wake regulation. Mol Psychiatry 2019; 24:1284-1295. [PMID: 30377299 PMCID: PMC6491268 DOI: 10.1038/s41380-018-0291-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 09/17/2018] [Accepted: 10/08/2018] [Indexed: 12/11/2022]
Abstract
Sleep and wakefulness control in the mammalian brain requires the coordination of various discrete interconnected neurons. According to the most conventional sleep model, wake-promoting neurons (WPNs) and sleep-promoting neurons (SPNs) compete for network dominance, creating a systematic "switch" that results in either the sleep or awake state. WPNs and SPNs are ubiquitous in the brainstem and diencephalon, areas that together contain <1% of the neurons in the human brain. Interestingly, many of these WPNs and SPNs co-express and co-release various types of the neurotransmitters that often have opposing modulatory effects on the network. Co-transmission is often beneficial to structures with limited numbers of neurons because it provides increasing computational capability and flexibility. Moreover, co-transmission allows subcortical structures to bi-directionally control postsynaptic neurons, thus helping to orchestrate several complex physiological functions such as sleep. Here, we present an in-depth review of co-transmission in hypothalamic WPNs and SPNs and discuss its functional significance in the sleep-wake network.
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Jancsik V, Bene R, Sótonyi P, Zachar G. Sub-cellular organization of the melanin-concentrating hormone neurons in the hypothalamus. Peptides 2018; 99:56-60. [PMID: 29108810 DOI: 10.1016/j.peptides.2017.11.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 10/30/2017] [Accepted: 11/02/2017] [Indexed: 12/22/2022]
Abstract
Melanin-concentrating hormone (MCH) is a potent orexigenic and sleep-promoting neuropeptide in mammals produced predominately by hypothalamic neurons which project to a wide variety of brain areas. Several MCH producing neurons contain MCH as the only neuropeptide, while others comprise cocaine- and amphetamine regulated transcript (CART) as well. The intrahypothalamic localization and the projection pattern of these two subpopulations are distinct. To provide structural grounding to understand the mechanism of action of MCH neurons we show here the subcellular localization of the neuropeptides in the two subpopulations within the hypothalamus of healthy young male mice by applying single and double immunofluorescence labelling.; Thick, prominent MCH immunopositive reticulation and fine discrete granules are detected within the perikarya of both CART positive and CART-free MCH neurons. Typically, one or more immunoreactive processes emanate from the perikarya. The bulk of CART immunoreactivity is also centrally positioned, surrounded by sparse immunoreactive granules within the perikarya and in the processes. In double immunopositive neurons, the two neuropeptides seem to colocalize in the heavily labelled central area, while the immunopositive granules in the cell body periphery and in the processes apparently contain either MCH or CART. This spatial arrangement suggests that MCH and CART, after being synthetized and processed in the endoplasmic reticulum/Golgi complex, are sorted into separate dense core vesicles, which then enter into the cell processes. This mechanism allows for both concerted and independent regulation of the transport and release of MCH and CART.
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Affiliation(s)
- Veronika Jancsik
- Department of Anatomy and Histology, University of Veterinary Medicine, Budapest, Hungary.
| | - Roland Bene
- Department of Anatomy and Histology, University of Veterinary Medicine, Budapest, Hungary
| | - Péter Sótonyi
- Department of Anatomy and Histology, University of Veterinary Medicine, Budapest, Hungary
| | - Gergely Zachar
- Department of Anatomy, Histology and Embryology, Semmelweis University Budapest, Hungary
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6
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Çavdar S, Özgür M, Çakmak YÖ, Kuvvet Y, Kunt SK, Sağlam G. Afferent projections of the subthalamic nucleus in the rat: emphasis on bilateral and interhemispheric connections. Acta Neurobiol Exp (Wars) 2018. [DOI: 10.21307/ane-2018-023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Abstract
Narcolepsy is a life-long, underrecognized sleep disorder that affects 0.02%-0.18% of the US and Western European populations. Genetic predisposition is suspected because of narcolepsy's strong association with HLA DQB1*06-02, and genome-wide association studies have identified polymorphisms in T-cell receptor loci. Narcolepsy pathophysiology is linked to loss of signaling by hypocretin-producing neurons; an autoimmune etiology possibly triggered by some environmental agent may precipitate hypocretin neuronal loss. Current treatment modalities alleviate the main symptoms of excessive daytime somnolence (EDS) and cataplexy and, to a lesser extent, reduce nocturnal sleep disruption, hypnagogic hallucinations, and sleep paralysis. Sodium oxybate (SXB), a sodium salt of γ hydroxybutyric acid, is a first-line agent for cataplexy and EDS and may help sleep disruption, hypnagogic hallucinations, and sleep paralysis. Various antidepressant medications including norepinephrine serotonin reuptake inhibitors, selective serotonin reuptake inhibitors, and tricyclic antidepressants are second-line agents for treating cataplexy. In addition to SXB, modafinil and armodafinil are first-line agents to treat EDS. Second-line agents for EDS are stimulants such as methylphenidate and extended-release amphetamines. Emerging therapies include non-hypocretin-based therapy, hypocretin-based treatments, and immunotherapy to prevent hypocretin neuronal death. Non-hypocretin-based novel treatments for narcolepsy include pitolisant (BF2.649, tiprolisant); JZP-110 (ADX-N05) for EDS in adults; JZP 13-005 for children; JZP-386, a deuterated sodium oxybate oral suspension; FT 218 an extended-release formulation of SXB; and JNJ-17216498, a new formulation of modafinil. Clinical trials are investigating efficacy and safety of SXB, modafinil, and armodafinil in children. γ-amino butyric acid (GABA) modulation with GABAA receptor agonists clarithromycin and flumazenil may help daytime somnolence. Other drugs investigated include GABAB agonists (baclofen), melanin-concentrating hormone antagonist, and thyrotropin-releasing hormone agonists. Hypocretin-based therapies include hypocretin peptide replacement administered either through an intracerebroventricular route or intranasal route. Hypocretin neuronal transplant and transforming stem cells into hypothalamic neurons are also discussed in this article. Immunotherapy to prevent hypocretin neuronal death is reviewed.
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Affiliation(s)
- Vivien C Abad
- Department of Psychiatry and Behavioral Sciences, Division of Sleep Medicine, Stanford University Outpatient Center, Redwood City, CA, USA
| | - Christian Guilleminault
- Department of Psychiatry and Behavioral Sciences, Division of Sleep Medicine, Stanford University Outpatient Center, Redwood City, CA, USA
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8
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Alachkar A, Alhassen L, Wang Z, Wang L, Onouye K, Sanathara N, Civelli O. Inactivation of the melanin concentrating hormone system impairs maternal behavior. Eur Neuropsychopharmacol 2016; 26:1826-1835. [PMID: 27617778 PMCID: PMC5929110 DOI: 10.1016/j.euroneuro.2016.08.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 08/05/2016] [Accepted: 08/24/2016] [Indexed: 01/22/2023]
Abstract
In order to prepare the mother for the demands of pregnancy and lactation, the maternal brain is subjected to a number of adaptations. Maternal behaviors are regulated by complex neuronal interactions. Here, we show that the melanin concentrating hormone (MCH) system is an important regulator of maternal behaviors. First, we report that melanin concentrating hormone receptor 1 knockout (MCHR1 KO) mice display a disruption of maternal behavior. Early postpartum MCHR1 KO females exhibit poor nesting, deficits in pup retrieval and maternal aggression. In addition, ablation of MCH receptors results in decreased milk production and prolactin mRNA levels. Then we show that these results are in line with those obtained in wild type mice (WT) treated with the specific MCHR1 antagonist GW803430. Furthermore, following pups retrieval, MCHR1 KO mice display a lower level of Fos expression than WT mice in the ventral tegmental area, and nucleus accumbens. With the progression of the lactation period, however, the MCHR1 KO mice improve maternal care towards their pups. This is manifested by an increase in the pups׳ survival rate and the decrease in pups׳ retrieval time beyond the second day after parturition. In conclusion, we show that the MCH system plays a significant role in the initiation of maternal behavior. In this context, MCH may play a role in integrating information from multiple sources, and connecting brain reward, homeostatic and regulatory systems.
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Affiliation(s)
- Amal Alachkar
- Departments of Pharmacology, School of Medicine, University of California, 369 Med Surge II, Irvine, CA 92697-4625, United States.
| | - Lamees Alhassen
- Departments of Pharmacology, School of Medicine, University of California, 369 Med Surge II, Irvine, CA 92697-4625, United States
| | - Zhiwei Wang
- Departments of Pharmacology, School of Medicine, University of California, 369 Med Surge II, Irvine, CA 92697-4625, United States
| | - Lien Wang
- Departments of Pharmacology, School of Medicine, University of California, 369 Med Surge II, Irvine, CA 92697-4625, United States
| | - Kara Onouye
- Departments of Pharmacology, School of Medicine, University of California, 369 Med Surge II, Irvine, CA 92697-4625, United States
| | - Nayna Sanathara
- Departments of Pharmacology, School of Medicine, University of California, 369 Med Surge II, Irvine, CA 92697-4625, United States
| | - Olivier Civelli
- Departments of Pharmacology, School of Medicine, University of California, 369 Med Surge II, Irvine, CA 92697-4625, United States; Pharmaceutical Sciences, School of Medicine, University of California, 369 Med Surge II, Irvine, CA 92697-4625, United States; Developmental and Cell Biology, School of Medicine, University of California, 369 Med Surge II, Irvine, CA 92697-4625, United States
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9
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Grace KP, Horner RL. Evaluating the Evidence Surrounding Pontine Cholinergic Involvement in REM Sleep Generation. Front Neurol 2015; 6:190. [PMID: 26388832 PMCID: PMC4555043 DOI: 10.3389/fneur.2015.00190] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2015] [Accepted: 08/17/2015] [Indexed: 11/13/2022] Open
Abstract
Rapid eye movement (REM) sleep - characterized by vivid dreaming, motor paralysis, and heightened neural activity - is one of the fundamental states of the mammalian central nervous system. Initial theories of REM sleep generation posited that induction of the state required activation of the "pontine REM sleep generator" by cholinergic inputs. Here, we review and evaluate the evidence surrounding cholinergic involvement in REM sleep generation. We submit that: (i) the capacity of pontine cholinergic neurotransmission to generate REM sleep has been firmly established by gain-of-function experiments, (ii) the function of endogenous cholinergic input to REM sleep generating sites cannot be determined by gain-of-function experiments; rather, loss-of-function studies are required, (iii) loss-of-function studies show that endogenous cholinergic input to the PTF is not required for REM sleep generation, and (iv) cholinergic input to the pontine REM sleep generating sites serve an accessory role in REM sleep generation: reinforcing non-REM-to-REM sleep transitions making them quicker and less likely to fail.
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Affiliation(s)
- Kevin P Grace
- Department of Medicine, University of Toronto , Toronto, ON , Canada
| | - Richard L Horner
- Department of Medicine, University of Toronto , Toronto, ON , Canada ; Department of Physiology, University of Toronto , Toronto, ON , Canada
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10
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Abstract
Sleep is expressed as a circadian rhythm and the two phenomena exist in a poorly understood relationship. Light affects each, simultaneously influencing rhythm phase and rapidly inducing sleep. Light has long been known to modulate sleep, but recent discoveries support its use as an effective nocturnal stimulus for eliciting sleep in certain rodents. “Photosomnolence” is mediated by classical and ganglion cell photoreceptors and occurs despite the ongoing high levels of locomotion at the time of stimulus onset. Brief photic stimuli trigger rapid locomotor suppression, sleep, and a large drop in core body temperature (Tc; Phase 1), followed by a relatively fixed duration interval of sleep (Phase 2) and recovery (Phase 3) to pre-sleep activity levels. Additional light can lengthen Phase 2. Potential retinal pathways through which the sleep system might be light-activated are described and the potential roles of orexin (hypocretin) and melanin-concentrating hormone are discussed. The visual input route is a practical avenue to follow in pursuit of the neural circuitry and mechanisms governing sleep and arousal in small nocturnal mammals and the organizational principles may be similar in diurnal humans. Photosomnolence studies are likely to be particularly advantageous because the timing of sleep is largely under experimenter control. Sleep can now be effectively studied using uncomplicated, nonintrusive methods with behavior evaluation software tools; surgery for EEG electrode placement is avoidable. The research protocol for light-induced sleep is easily implemented and useful for assessing the effects of experimental manipulations on the sleep induction pathway. Moreover, the experimental designs and associated results benefit from a substantial amount of existing neuroanatomical and pharmacological literature that provides a solid framework guiding the conduct and interpretation of future investigations.
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11
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Larson-Prior LJ, Ju YE, Galvin JE. Cortical-subcortical interactions in hypersomnia disorders: mechanisms underlying cognitive and behavioral aspects of the sleep-wake cycle. Front Neurol 2014; 5:165. [PMID: 25309500 PMCID: PMC4160996 DOI: 10.3389/fneur.2014.00165] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Accepted: 08/18/2014] [Indexed: 01/01/2023] Open
Abstract
Subcortical circuits mediating sleep–wake functions have been well characterized in animal models, and corroborated by more recent human studies. Disruptions in these circuits have been identified in hypersomnia disorders (HDs) such as narcolepsy and Kleine–Levin Syndrome, as well as in neurodegenerative disorders expressing excessive daytime sleepiness. However, the behavioral expression of sleep–wake functions is not a simple on-or-off state determined by subcortical circuits, but encompasses a complex range of behaviors determined by the interaction between cortical networks and subcortical circuits. While conceived as disorders of sleep, HDs are equally disorders of wake, representing a fundamental instability in neural state characterized by lapses of alertness during wake. These episodic lapses in alertness and wakefulness are also frequently seen in neurodegenerative disorders where electroencephalogram demonstrates abnormal function in cortical regions associated with cognitive fluctuations (CFs). Moreover, functional connectivity MRI shows instability of cortical networks in individuals with CFs. We propose that the inability to stabilize neural state due to disruptions in the sleep–wake control networks is common to the sleep and cognitive dysfunctions seen in hypersomnia and neurodegenerative disorders.
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Affiliation(s)
- Linda J Larson-Prior
- Department of Radiology, Washington University School of Medicine , St. Louis, MO , USA ; Department of Neurology, Washington University School of Medicine , St. Louis, MO , USA
| | - Yo-El Ju
- Department of Neurology, Washington University School of Medicine , St. Louis, MO , USA
| | - James E Galvin
- Departments of Neurology, New York University Langone School of Medicine , New York, NY , USA ; Department of Psychiatry, New York University Langone School of Medicine , New York, NY , USA ; Department of Population Health, New York University Langone School of Medicine , New York, NY , USA
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12
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Affiliation(s)
- Sonia Jego
- Douglas Institute, Department of Psychiatry, McGill University, Montreal, Canada
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13
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Szymusiak RS. New Insights into Melanin Concentrating Hormone and Sleep: A Critical Topics Forum. Sleep 2013. [DOI: 10.5665/sleep.3184] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Affiliation(s)
- Ronald S. Szymusiak
- Research Service, V.A. Greater Los Angeles Healthcare System and Departments of Medicine and Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, CA
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14
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Blouin AM, Siegel JM. Relation of melanin concentrating hormone levels to sleep, emotion and hypocretin levels. Sleep 2013; 36:1777. [PMID: 24293749 DOI: 10.5665/sleep.3194] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Affiliation(s)
- Ashley M Blouin
- Department of Metabolism and Aging and Department of Neuroscience, The Scripps Research Institute, Jupiter, FL
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15
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Pelluru D, Konadhode R, Shiromani PJ. MCH neurons are the primary sleep-promoting group. Sleep 2013; 36:1779-81. [PMID: 24293750 DOI: 10.5665/sleep.3196] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Affiliation(s)
- Dheeraj Pelluru
- Ralph H. Johnson VA and Medical University of South Carolina, Charleston, SC
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