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Machado NL, Todd WD, Kaur S, Saper CB. Median preoptic GABA and glutamate neurons exert differential control over sleep behavior. Curr Biol 2022; 32:2011-2021.e3. [PMID: 35385692 PMCID: PMC9090993 DOI: 10.1016/j.cub.2022.03.039] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 11/10/2021] [Accepted: 03/13/2022] [Indexed: 12/13/2022]
Abstract
Previous studies suggest that the median preoptic nucleus (MnPO) of the hypothalamus plays an important role in regulating the wake-sleep cycle and, in particular, homeostatic sleep drive. However, the precise cellular phenotypes, targets, and central mechanisms by which the MnPO neurons regulate the wake-sleep cycle remain unknown. Both excitatory and inhibitory MnPO neurons innervate brain regions implicated in sleep promotion and maintenance, suggesting that both cell types may participate in sleep control. Using genetically targeted approaches, we investigated the role of the MnPO GABAergic (MnPOVgat) and glutamatergic (MnPOVglut2) neurons in modulating wake-sleep behavior of mice. We found that both neuron populations differentially participate in wake-sleep control, with MnPOVgat neurons being involved in sleep homeostasis and MnPOVglut2 neurons facilitating sleep during allostatic (stressful) challenges.
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2
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Kostin A, Alam MA, McGinty D, Alam MN. Adult hypothalamic neurogenesis and sleep-wake dysfunction in aging. Sleep 2021; 44:5986548. [PMID: 33202015 DOI: 10.1093/sleep/zsaa173] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 07/22/2020] [Indexed: 12/21/2022] Open
Abstract
In the mammalian brain, adult neurogenesis has been extensively studied in the hippocampal sub-granular zone and the sub-ventricular zone of the anterolateral ventricles. However, growing evidence suggests that new cells are not only "born" constitutively in the adult hypothalamus, but many of these cells also differentiate into neurons and glia and serve specific functions. The preoptic-hypothalamic area plays a central role in the regulation of many critical functions, including sleep-wakefulness and circadian rhythms. While a role for adult hippocampal neurogenesis in regulating hippocampus-dependent functions, including cognition, has been extensively studied, adult hypothalamic neurogenic process and its contributions to various hypothalamic functions, including sleep-wake regulation are just beginning to unravel. This review is aimed at providing the current understanding of the hypothalamic adult neurogenic processes and the extent to which it affects hypothalamic functions, including sleep-wake regulation. We propose that hypothalamic neurogenic processes are vital for maintaining the proper functioning of the hypothalamic sleep-wake and circadian systems in the face of regulatory challenges. Sleep-wake disturbance is a frequent and challenging problem of aging and age-related neurodegenerative diseases. Aging is also associated with a decline in the neurogenic process. We discuss a hypothesis that a decrease in the hypothalamic neurogenic process underlies the aging of its sleep-wake and circadian systems and associated sleep-wake disturbance. We further discuss whether neuro-regenerative approaches, including pharmacological and non-pharmacological stimulation of endogenous neural stem and progenitor cells in hypothalamic neurogenic niches, can be used for mitigating sleep-wake and other hypothalamic dysfunctions in aging.
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Affiliation(s)
- Andrey Kostin
- Research Service (151A3), Veterans Affairs Greater Los Angeles Healthcare System, Sepulveda, CA
| | - Md Aftab Alam
- Research Service (151A3), Veterans Affairs Greater Los Angeles Healthcare System, Sepulveda, CA.,Department of Psychiatry, University of California, Los Angeles, CA
| | - Dennis McGinty
- Research Service (151A3), Veterans Affairs Greater Los Angeles Healthcare System, Sepulveda, CA.,Department of Psychology, University of California, Los Angeles, CA
| | - Md Noor Alam
- Research Service (151A3), Veterans Affairs Greater Los Angeles Healthcare System, Sepulveda, CA.,Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA
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3
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Reitz SL, Kelz MB. Preoptic Area Modulation of Arousal in Natural and Drug Induced Unconscious States. Front Neurosci 2021; 15:644330. [PMID: 33642991 PMCID: PMC7907457 DOI: 10.3389/fnins.2021.644330] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Accepted: 01/26/2021] [Indexed: 12/12/2022] Open
Abstract
The role of the hypothalamic preoptic area (POA) in arousal state regulation has been studied since Constantin von Economo first recognized its importance in the early twentieth century. Over the intervening decades, the POA has been shown to modulate arousal in both natural (sleep and wake) as well as drug-induced (anesthetic-induced unconsciousness) states. While the POA is well known for its role in sleep promotion, populations of wake-promoting neurons within the region have also been identified. However, the complexity and molecular heterogeneity of the POA has made distinguishing these two populations difficult. Though multiple lines of evidence demonstrate that general anesthetics modulate the activity of the POA, the region's heterogeneity has also made it challenging to determine whether the same neurons involved in sleep/wake regulation also modulate arousal in response to general anesthetics. While a number of studies show that sleep-promoting POA neurons are activated by various anesthetics, recent work suggests this is not universal to all arousal-regulating POA neurons. Technical innovations are making it increasingly possible to classify and distinguish the molecular identities of neurons involved in sleep/wake regulation as well as anesthetic-induced unconsciousness. Here, we review the current understanding of the POA's role in arousal state regulation of both natural and drug-induced forms of unconsciousness, including its molecular organization and connectivity to other known sleep and wake promoting regions. Further insights into the molecular identities and connectivity of arousal-regulating POA neurons will be critical in fully understanding how this complex region regulates arousal states.
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Affiliation(s)
- Sarah L. Reitz
- Department of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Mahoney Institute for Neurosciences, University of Pennsylvania, Philadelphia, PA, United States
- Circadian and Sleep Institute, University of Pennsylvania, Philadelphia, PA, United States
| | - Max B. Kelz
- Department of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Mahoney Institute for Neurosciences, University of Pennsylvania, Philadelphia, PA, United States
- Circadian and Sleep Institute, University of Pennsylvania, Philadelphia, PA, United States
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4
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Simmons SJ, Gentile TA. Cocaine abuse and midbrain circuits: Functional anatomy of hypocretin/orexin transmission and therapeutic prospect. Brain Res 2020; 1731:146164. [PMID: 30796894 PMCID: PMC6702109 DOI: 10.1016/j.brainres.2019.02.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 01/09/2019] [Accepted: 02/12/2019] [Indexed: 12/18/2022]
Abstract
Cocaine abuse remains a pervasive public health problem, and treatments thus far have proven ineffective for long-term abstinence maintenance. Intensive research on the neurobiology underlying drug abuse has led to the consideration of many candidate transmitter systems to target for intervention. Among these, the hypocretin/orexin (hcrt/ox) neuropeptide system holds largely untapped yet clinically viable therapeutic potential. Hcrt/ox originates from the hypothalamus and projects widely across the mammalian central nervous system to produce neuroexcitatory actions via two excitatory G-protein coupled receptor subtypes. Functionally, hcrt/ox promotes arousal/wakefulness and facilitates energy homeostasis. In the early 2000s, hcrt/ox transmission was shown to underlie mating behavior in male rats suggesting a novel role in reward-seeking. Soon thereafter, hcrt/ox neurons were shown to respond to drug-associated stimuli, and hcrt/ox transmission was found to facilitate motivated responding for intravenous cocaine. Notably, blocking hcrt/ox transmission using systemic or site-directed pharmacological antagonists markedly reduced motivated drug-taking as well as drug-seeking in tests of relapse. This review will unfold the current state of knowledge implicating hcrt/ox receptor transmission in the context of cocaine abuse and provide detailed background on animal models and underlying midbrain circuits. Specifically, attention will be paid to the mesoaccumbens, tegmental, habenular, pallidal and preoptic circuits. The review will conclude with discussion of recent preclinical studies assessing utility of suvorexant - the first and only FDA-approved hcrt/ox receptor antagonist - against cocaine-associated behaviors.
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Affiliation(s)
- Steven J Simmons
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia Research Institute, Philadelphia, PA, USA; Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA.
| | - Taylor A Gentile
- Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
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5
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Alam MA, Kostin A, Siegel J, McGinty D, Szymusiak R, Alam MN. Characteristics of sleep-active neurons in the medullary parafacial zone in rats. Sleep 2019; 41:5050231. [PMID: 29986116 DOI: 10.1093/sleep/zsy130] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Indexed: 12/21/2022] Open
Abstract
Growing evidence supports a role for the medullary parafacial zone in non-rapid eye movement (non-REM) sleep regulation. Cell-body specific lesions of the parafacial zone or disruption of its GABAergic/glycinergic transmission causes suppression of non-REM sleep, whereas, targeted activation of parafacial GABAergic/glycinergic neurons reduce sleep latency and increase non-REM sleep amount, bout duration, and cortical electroencephalogram (EEG) slow-wave activity. Parafacial GABAergic/glycinergic neurons also express sleep-associated c-fos immunoreactivity. Currently, it is not clear if parafacial neurons are non-REM sleep-active and/or REM sleep-active or play a role in the initiation or maintenance of non-REM sleep. We recorded extracellular discharge activity of parafacial neurons across the spontaneous sleep-waking cycle using microwire technique in freely behaving rats. Waking-, non-REM sleep-, and REM sleep-active neuronal groups were segregated by the ratios of their discharge rate changes during non-REM and REM sleep versus waking and non-REM sleep versus REM sleep. Parafacial neurons exhibited heterogeneity in sleep-waking discharge patterns, but 34 of 86 (40%) recorded neurons exhibited increased discharge rate during non-REM sleep compared to waking. These neurons also exhibited increased discharge prior to non-REM sleep onset, similar to median preoptic nucleus (MnPO) and ventrolateral preoptic area (VLPO) sleep-active neurons. However, unlike MnPO and VLPO sleep-active neurons, parafacial neurons were weakly-moderately sleep-active and exhibited a stable rather than decreasing discharge across sustained non-REM sleep episode. We show for the first time that the medullary parafacial zone contains non-REM sleep-active neurons. These neurons are likely functionally important brainstem compliments to the preoptic-hypothalamic sleep-promoting neuronal networks that underlie sleep onset and maintenance.
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Affiliation(s)
- Md Aftab Alam
- Research Service (151A3), Veterans Affairs Greater Los Angeles Healthcare System, Sepulveda, CA.,Department of Psychiatry, University of California, Los Angeles, CA
| | - Andrey Kostin
- Research Service (151A3), Veterans Affairs Greater Los Angeles Healthcare System, Sepulveda, CA
| | - Jerome Siegel
- Research Service (151A3), Veterans Affairs Greater Los Angeles Healthcare System, Sepulveda, CA.,Department of Psychiatry, University of California, Los Angeles, CA
| | - Dennis McGinty
- Research Service (151A3), Veterans Affairs Greater Los Angeles Healthcare System, Sepulveda, CA.,Department of Psychology, University of California, Los Angeles, CA
| | - Ronald Szymusiak
- Research Service (151A3), Veterans Affairs Greater Los Angeles Healthcare System, Sepulveda, CA.,Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA
| | - Md Noor Alam
- Research Service (151A3), Veterans Affairs Greater Los Angeles Healthcare System, Sepulveda, CA.,Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA
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6
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Kurt G, Woodworth HL, Fowler S, Bugescu R, Leinninger GM. Activation of lateral hypothalamic area neurotensin-expressing neurons promotes drinking. Neuropharmacology 2018; 154:13-21. [PMID: 30266601 DOI: 10.1016/j.neuropharm.2018.09.038] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Revised: 09/04/2018] [Accepted: 09/24/2018] [Indexed: 12/18/2022]
Abstract
Animals must ingest water via drinking to maintain fluid homeostasis, yet the neurons that specifically promote drinking behavior are incompletely characterized. The lateral hypothalamic area (LHA) as a whole is essential for drinking behavior but most LHA neurons indiscriminately promote drinking and feeding. By contrast, activating neurotensin (Nts)-expressing LHA neurons (termed LHA Nts neurons) causes mice to immediately drink water with a delayed suppression of feeding. We therefore hypothesized that LHA Nts neurons are sufficient to induce drinking behavior and that these neurons specifically bias for fluid intake over food intake. To test this hypothesis we used designer receptors exclusively activated by designer drugs (DREADDs) to selectively activate LHA Nts neurons and studied the impact on fluid intake, fluid preference and feeding. Activation of LHA Nts neurons stimulated drinking in water-replete and dehydrated mice, indicating that these neurons are sufficient to promote water intake regardless of homeostatic need. Interestingly, mice with activated LHA Nts neurons drank any fluid that was provided regardless of its palatability, but if given a choice they preferred water or palatable solutions over unpalatable (quinine) or dehydrating (hypertonic saline) solutions. Notably, acute activation of LHA Nts neurons robustly promoted fluid but not food intake. Overall, our study confirms that activation of LHA Nts neurons is sufficient to induce drinking behavior and biases for fluid intake. Hence, LHA Nts neurons may be important targets for orchestrating the appropriate ingestive behavior necessary to maintain fluid homeostasis. This article is part of the Special Issue entitled 'Hypothalamic Control of Homeostasis'.
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Affiliation(s)
- Gizem Kurt
- Department of Physiology, Michigan State University, East Lansing, MI, 48114, USA
| | - Hillary L Woodworth
- Department of Physiology, Michigan State University, East Lansing, MI, 48114, USA
| | - Sabrina Fowler
- Department of Physiology, Michigan State University, East Lansing, MI, 48114, USA
| | - Raluca Bugescu
- Department of Physiology, Michigan State University, East Lansing, MI, 48114, USA
| | - Gina M Leinninger
- Department of Physiology, Michigan State University, East Lansing, MI, 48114, USA.
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McKinley MJ, Yao ST, Uschakov A, McAllen RM, Rundgren M, Martelli D. The median preoptic nucleus: front and centre for the regulation of body fluid, sodium, temperature, sleep and cardiovascular homeostasis. Acta Physiol (Oxf) 2015; 214:8-32. [PMID: 25753944 DOI: 10.1111/apha.12487] [Citation(s) in RCA: 129] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 03/04/2015] [Accepted: 03/05/2015] [Indexed: 12/19/2022]
Abstract
Located in the midline anterior wall of the third cerebral ventricle (i.e. the lamina terminalis), the median preoptic nucleus (MnPO) receives a unique set of afferent neural inputs from fore-, mid- and hindbrain. These afferent connections enable it to receive neural signals related to several important aspects of homeostasis. Included in these afferent projections are (i) neural inputs from two adjacent circumventricular organs, the subfornical organ and organum vasculosum laminae terminalis, that respond to hypertonicity, circulating angiotensin II or other humoural factors, (ii) signals from cutaneous warm and cold receptors that are relayed to MnPO, respectively, via different subnuclei in the lateral parabrachial nucleus and (iii) input from the medulla associated with baroreceptor and vagal afferents. These afferent signals reach appropriate neurones within the MnPO that enable relevant neural outputs, both excitatory and inhibitory, to be activated or inhibited. The efferent neural pathways that proceed from the MnPO terminate on (i) neuroendocrine cells in the hypothalamic supraoptic and paraventricular nuclei to regulate vasopressin release, while polysynaptic pathways from MnPO to cortical sites may drive thirst and water intake, (ii) thermoregulatory pathways to the dorsomedial hypothalamic nucleus and medullary raphé to regulate shivering, brown adipose tissue and skin vasoconstriction, (iii) parvocellular neurones in the hypothalamic paraventricular nucleus that drive autonomic pathways influencing cardiovascular function. As well, (iv) other efferent pathways from the MnPO to sites in the ventrolateral pre-optic nucleus, perifornical region of the lateral hypothalamic area and midbrain influence sleep mechanisms.
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Affiliation(s)
- M. J. McKinley
- Florey Institute of Neuroscience and Mental Health; University of Melbourne; Melbourne Vic. Australia
- Department of Physiology; University of Melbourne; Melbourne Vic. Australia
| | - S. T. Yao
- Florey Institute of Neuroscience and Mental Health; University of Melbourne; Melbourne Vic. Australia
| | - A. Uschakov
- Florey Institute of Neuroscience and Mental Health; University of Melbourne; Melbourne Vic. Australia
| | - R. M. McAllen
- Florey Institute of Neuroscience and Mental Health; University of Melbourne; Melbourne Vic. Australia
- Department of Anatomy and Neuroscience; University of Melbourne; Melbourne Vic. Australia
| | - M. Rundgren
- Department of Physiology and Pharmacology; Karolinska Institutet; Stockholm Sweden
| | - D. Martelli
- Florey Institute of Neuroscience and Mental Health; University of Melbourne; Melbourne Vic. Australia
- Department of Biomedical and Neuromotor Science; University of Bologna; Bologna Italy
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8
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Kumar S, Rai S, Hsieh KC, McGinty D, Alam MN, Szymusiak R. Adenosine A(2A) receptors regulate the activity of sleep regulatory GABAergic neurons in the preoptic hypothalamus. Am J Physiol Regul Integr Comp Physiol 2013; 305:R31-41. [PMID: 23637137 DOI: 10.1152/ajpregu.00402.2012] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The median preoptic nucleus (MnPN) and the ventrolateral preoptic area (VLPO) are two hypothalamic regions that have been implicated in sleep regulation, and both nuclei contain sleep-active GABAergic neurons. Adenosine is an endogenous sleep regulatory substance, which promotes sleep via A1 and A2A receptors (A2AR). Infusion of A2AR agonist into the lateral ventricle or into the subarachnoid space underlying the rostral basal forebrain (SS-rBF), has been previously shown to increase sleep. We examined the effects of an A2AR agonist, CGS-21680, administered into the lateral ventricle and the SS-rBF on sleep and c-Fos protein immunoreactivity (Fos-IR) in GABAergic neurons in the MnPN and VLPO. Intracerebroventricular administration of CGS-21680 during the second half of lights-on phase increased sleep and increased the number of MnPN and VLPO GABAergic neurons expressing Fos-IR. Similar effects were found with CGS-21680 microinjection into the SS-rBF. The induction of Fos-IR in preoptic GABAergic neurons was not secondary to drug-induced sleep, since CGS-21680 delivered to the SS-rBF significantly increased Fos-IR in MnPN and VLPO neurons in animals that were not permitted to sleep. Intracerebroventricular infusion of ZM-241385, an A2AR antagonist, during the last 2 h of a 3-h period of sleep deprivation caused suppression of subsequent recovery sleep and reduced Fos-IR in MnPN and VLPO GABAergic neurons. Our findings support a hypothesis that A2AR-mediated activation of MnPN and VLPO GABAergic neurons contributes to adenosinergic regulation of sleep.
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Affiliation(s)
- Sunil Kumar
- Research Service, Veteran Affairs Greater Los Angeles Healthcare System, Sepulveda, CA, USA
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9
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Moffett SX, Giannopoulos PF, James TD, Martin JV. Effects of acute microinjections of thyroid hormone to the preoptic region of hypothyroid adult male rats on sleep, motor activity and body temperature. Brain Res 2013; 1516:55-65. [PMID: 23603414 DOI: 10.1016/j.brainres.2013.04.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Revised: 04/05/2013] [Accepted: 04/07/2013] [Indexed: 01/28/2023]
Abstract
Thyroid hormones induce short-latency nongenomic effects in adult brain tissue, suggesting that their acute administration would affect brain activity in intact animals. The influence on EEG-defined sleep of acute restoration of l-3,3'5-triiodothyronine (T3) to a sleep-regulatory brain region, the preoptic region, was examined in hypothyroid rats. Sleep parameters were monitored for 48 h weekly: for 24 h immediately following a control microinjection and for an additional 24h after a second microinjection including a T3 dose to the preoptic region or lateral ventricle. Male albino rats were implanted with EEG and EMG electrodes, abdominal temperature/activity transponders and unilateral lateral ventricle cannulae or bilateral preoptic region cannulae, and were given 0.02% n-propythiouracil (PTU) in their drinking water for 4 weeks. For histologically-confirmed bilateral preoptic region cannula placements (N=7), effects of T3 (especially a 3 μg dose) were apparent within 10h of injection as decreases in REM, NREM and total sleep and increases in waking and activity. Minimal effects of lateral ventricle T3 microinjection were demonstrated (N=5). Significant effects due to the time of day on the experimental measures were seen in both lateral ventricle and preoptic region groups, but these effects did not interact with the effect of administered hormone dose. These effects of T3 microinjection to the preoptic region were demonstrated after acute injections and within hours of injection rather than after chronic administration over days.
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Affiliation(s)
- Steven X Moffett
- Department of Biology, Rutgers University, Camden, NJ 08055, USA
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10
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GABAergic processes within the median preoptic nucleus promote NREM sleep. Behav Brain Res 2012; 232:60-5. [DOI: 10.1016/j.bbr.2012.03.033] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Revised: 03/12/2012] [Accepted: 03/16/2012] [Indexed: 01/04/2023]
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11
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Hsieh KC, Gvilia I, Kumar S, Uschakov A, McGinty D, Alam MN, Szymusiak R. c-Fos expression in neurons projecting from the preoptic and lateral hypothalamic areas to the ventrolateral periaqueductal gray in relation to sleep states. Neuroscience 2011; 188:55-67. [PMID: 21601616 PMCID: PMC3140960 DOI: 10.1016/j.neuroscience.2011.05.016] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2011] [Revised: 05/06/2011] [Accepted: 05/09/2011] [Indexed: 01/30/2023]
Abstract
The ventrolateral division of the periaqueductal gray (vlPAG) and the adjacent deep mesencephalic reticular nucleus have been implicated in the control of sleep. The preoptic hypothalamus, which contains populations of sleep-active neurons, is an important source of afferents to the vlPAG. The perifornical lateral hypothalamus (LH) contains populations of wake-active neurons and also projects strongly to the vlPAG. We examined nonREM and REM sleep-dependent expression of c-Fos protein in preoptic-vlPAG and LH-vlPAG projection neurons identified by retrograde labeling with Fluorogold (FG). Separate groups of rats (n=5) were subjected to 3 h total sleep deprivation (TSD) followed by 1 h recovery sleep (RS), or to 3 h of selective REM sleep deprivation (RSD) followed by RS. A third group of rats (n=5) was subjected to TSD without opportunity for RS (awake group). In the median preoptic nucleus (MnPN), the percentage of FG+ neurons that were also Fos+ was higher in TSD-RS animals compared to both RSD-RS rats and awake rats. There were significant correlations between time spent in deep nonREM sleep during the 1 h prior to sacrifice across groups and the percentage of double-labeled cells in MnPN and ventrolateral preoptic area (VLPO). There were no significant correlations between percentage of double-labeled neurons and time spent in REM sleep for any of the preoptic nuclei examined. In the LH, percentage of double-labeled neurons was highest in awake rats, intermediate in TSD-RS rats and lowest in the RSD-RS group. These results suggest that neurons projecting from MnPN and VLPO to the vlPAG are activated during nonREM sleep and support the hypothesis that preoptic neurons provide inhibitory input to vlPAG during sleep. Suppression of excitatory input to the vlPAG from the LH during sleep may have a permissive effect on REM sleep generation.
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Affiliation(s)
- Kung-Chiao Hsieh
- Research Service, V.A. Greater Los Angeles
- Departments of Medicine and Neurobiology, UCLA School of Medicine
| | - Irma Gvilia
- Research Service, V.A. Greater Los Angeles
- Beritashvili Institute of Physiology, Georgia
| | - Sunil Kumar
- Research Service, V.A. Greater Los Angeles
- Departments of Medicine and Neurobiology, UCLA School of Medicine
| | - Aaron Uschakov
- Research Service, V.A. Greater Los Angeles
- Departments of Medicine and Neurobiology, UCLA School of Medicine
| | - Dennis McGinty
- Research Service, V.A. Greater Los Angeles
- Department of Psychology, UCLA
| | - M. Noor Alam
- Research Service, V.A. Greater Los Angeles
- Department of Psychology, UCLA
| | - Ronald Szymusiak
- Research Service, V.A. Greater Los Angeles
- Departments of Medicine and Neurobiology, UCLA School of Medicine
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12
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Kostin A, Rai S, Kumar S, Szymusiak R, McGinty D, Alam MN. Nitric oxide production in the perifornical-lateral hypothalamic area and its influences on the modulation of perifornical-lateral hypothalamic area neurons. Neuroscience 2011; 179:159-69. [PMID: 21277356 PMCID: PMC3059372 DOI: 10.1016/j.neuroscience.2011.01.052] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Revised: 01/05/2011] [Accepted: 01/23/2011] [Indexed: 10/18/2022]
Abstract
The perifornical-lateral hypothalamic area (PF-LHA) is a major wake-promoting structure. It predominantly contains neurons that are active during behavioral and cortical activation. PF-LHA stimulation produces arousal and PF-LHA lesions produce somnolence. Nitric oxide (NO) is a gaseous neurotransmitter that has been implicated in the regulation of multiple pathological and physiological processes including the regulation of sleep. NO levels are higher in the cortex and in the basal forebrain (BF) during arousal. In this study we determined whether NO levels increase in the PF-LHA during prolonged arousal and whether increased NO modulates the discharge activity of PF-LHA neurons. Experiments were conducted during lights-on phase between 8.00 and 20.00 h (lights-on at 8.00 h). First, we quantified levels of NO metabolites, NO2- and NO3- (collectively called NOx-) in the microdialysis dialysates collected from the PF-LHA during baseline (undisturbed rats), 6 h of sleep deprivation (SD), and recovery after SD. We further determined the effects of a NO donor, NOC-18, on the discharge activity of PF-LHA neurons in urethane-anesthetized rats. Overall, SD significantly affected NOx- production in the PF-LHA (one way repeated measures ANOVA, F=7.827, P=0.004). The levels of NOx- increased progressively in animals that were subjected to prolonged arousal as compared to the undisturbed predominantly sleeping animals and decreased during the recovery period. Local application of NOC-18 significantly suppressed the discharge of PF-LHA neurons including a majority of stimulus-on neurons or neurons exhibiting activation during electroencephalogram (EEG) desynchronization. The findings of this study suggest that in the PF-LHA, NO production is elevated during prolonged waking and that NO exerts predominantly inhibitory effects on PF-LHA neurons, especially on those neurons that are active during cortical activation. These findings are consistent with a hypothesis that NO in the PF-LHA plays a role in sleep regulation by inhibiting its neurons.
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Affiliation(s)
- Andrey Kostin
- Research Service, Veterans Affairs Greater Los Angeles Healthcare System, Sepulveda, California, USA
- Department of Medicine, School of Medicine, University of California, Los Angeles, California, USA
| | - Seema Rai
- Research Service, Veterans Affairs Greater Los Angeles Healthcare System, Sepulveda, California, USA
| | - Sunil Kumar
- Research Service, Veterans Affairs Greater Los Angeles Healthcare System, Sepulveda, California, USA
| | - Ronald Szymusiak
- Research Service, Veterans Affairs Greater Los Angeles Healthcare System, Sepulveda, California, USA
- Department of Medicine, School of Medicine, University of California, Los Angeles, California, USA
- Department of Neurobiology, School of Medicine, University of California, Los Angeles, California, USA
| | - Dennis McGinty
- Research Service, Veterans Affairs Greater Los Angeles Healthcare System, Sepulveda, California, USA
- Department of Psychology, University of California, Los Angeles, Los Angeles, California, USA
| | - Md. Noor Alam
- Research Service, Veterans Affairs Greater Los Angeles Healthcare System, Sepulveda, California, USA
- Department of Medicine, School of Medicine, University of California, Los Angeles, California, USA
- Department of Psychology, University of California, Los Angeles, Los Angeles, California, USA
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Alam MN, Kumar S, Suntsova N, Bashir T, Szymusiak R, McGinty D. GABAergic regulation of the perifornical-lateral hypothalamic neurons during non-rapid eye movement sleep in rats. Neuroscience 2010; 167:920-8. [PMID: 20188152 PMCID: PMC2854202 DOI: 10.1016/j.neuroscience.2010.02.038] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2010] [Revised: 02/11/2010] [Accepted: 02/13/2010] [Indexed: 01/20/2023]
Abstract
The perifornical-lateral hypothalamic area (PF-LHA) has been implicated in the regulation of behavioral arousal. The PF-LHA predominantly contains neurons that are active during behavioral and cortical activation and quiescent during non-rapid eye movement (nonREM) sleep, that is, are nonREM-off neurons. Some in vitro and in vivo studies indicate that PF-LHA neurons, including hypocretin-expressing neurons, are under GABAergic control. However, a role of GABA in suppressing the discharge of PF-LHA neurons during spontaneous nonREM sleep has not been confirmed. We recorded the sleep-wake discharge profiles of PF-LHA neurons and simultaneously assessed the contributions of local GABA(A) receptor activation and blockade on their wake- and nonREM sleep-related discharge activities by delivering GABA(A) receptor agonist, muscimol (500 nm, 5 microM, and 10 microM) and its antagonist, bicuculline (5 microM, 10 microM, and 20 microM), adjacent to the recorded neurons via reverse microdialysis. Muscimol dose-dependently decreased the discharge of PF-LHA neurons including nonREM-off neurons. Muscimol-induced suppression of discharge during nonREM sleep was significantly weaker than the suppression produced during waking. In the presence of bicuculline, PF-LHA neurons, including nonREM-off neurons, exhibited elevated discharge, which was dose-dependent and was significantly higher during nonREM sleep, compared to waking. These results suggest that GABA(A) receptor mediated increased GABAergic tone contributes to the suppression of PF-LHA neurons, including nonREM-off neurons, during spontaneous nonREM sleep.
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Affiliation(s)
- M N Alam
- Research Service, Veterans Affairs Greater Los Angeles Healthcare System, Sepulveda, CA 91343, USA.
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Hahn JD, Swanson LW. Distinct patterns of neuronal inputs and outputs of the juxtaparaventricular and suprafornical regions of the lateral hypothalamic area in the male rat. ACTA ACUST UNITED AC 2010; 64:14-103. [PMID: 20170674 DOI: 10.1016/j.brainresrev.2010.02.002] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Revised: 02/09/2010] [Accepted: 02/10/2010] [Indexed: 12/26/2022]
Abstract
We have analyzed at high resolution the neuroanatomical connections of the juxtaparaventricular region of the lateral hypothalamic area (LHAjp); as a control and in comparison to this, we also performed a preliminary analysis of a nearby LHA region that is dorsal to the fornix, namely the LHA suprafornical region (LHAs). The connections of these LHA regions were revealed with a coinjection tract-tracing technique involving a retrograde (cholera toxin B subunit) and anterograde (Phaseolus vulgaris leucoagglutinin) tracer. The LHAjp and LHAs together connect with almost every major division of the cerebrum and cerebrospinal trunk, but their connection profiles are markedly different and distinct. In simple terms, the connections of the LHAjp indicate a possible primary role in the modulation of defensive behavior; for the LHAs, a role in the modulation of ingestive behavior is suggested. However, the relation of the LHAjp and LHAs to potential modulation of these behaviors, as indicated by their neuroanatomical connections, appears to be highly integrative as it includes each of the major functional divisions of the nervous system that together determine behavior, i.e., cognitive, state, sensory, and motor. Furthermore, although a primary role is indicated for each region with respect to a particular mode of behavior, intermode modulation of behavior is also indicated. In summary, the extrinsic connections of the LHAjp and LHAs (so far as we have described them) suggest that these regions have a profoundly integrative role in which they may participate in the orchestrated modulation of elaborate behavioral repertoires.
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Affiliation(s)
- Joel D Hahn
- Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089-2520, USA.
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Torterolo P, Benedetto L, Lagos P, Sampogna S, Chase MH. State-dependent pattern of Fos protein expression in regionally-specific sites within the preoptic area of the cat. Brain Res 2009; 1267:44-56. [DOI: 10.1016/j.brainres.2009.02.054] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2008] [Revised: 02/17/2009] [Accepted: 02/18/2009] [Indexed: 11/26/2022]
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