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Liu G, Zhang Y, Zhang W, Wu X, Jiang H, Zhang X. Validation of the relationship between rapid eye movement sleep and sleep-related erections in healthy adults by a feasible instrument Fitbit Charge2. Andrology 2024; 12:365-373. [PMID: 37300476 DOI: 10.1111/andr.13478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 04/30/2023] [Accepted: 06/05/2023] [Indexed: 06/12/2023]
Abstract
BACKGROUND Sleep, particularly rapid eye movement sleep, has been found to be associated with sleep-related erections. While RigiScan is currently a more accurate method for monitoring nocturnal erectile events, the Fitbit, a smart wearable device, shows great potential for sleep monitoring. OBJECTIVES To analyze the relationship between sleep-related erections and sleep by recruiting sexually active, healthy men for simultaneous monitoring of sleep and nocturnal penile tumescence and rigidity. PATIENTS AND METHODS Using Fitbit Charge2 and RigiScan, we simultaneously monitored nocturnal sleep and erections in 43 healthy male volunteers, and analyzed the relationship between sleep periods and erectile events with the Statistical Package for Social Sciences. RESULTS Among all erectile events, 89.8% were related to rapid eye movement, and 79.2% of all rapid eye movement periods were associated with erectile events. Moreover, a statistical correlation was shown between the duration of rapid eye movement and the time of total erectile events (first night: 𝜌 = 0.316, p = 0.039; second night: 𝜌 = 0.370, p = 0.015). DISCUSSION AND CONCLUSION Our study shows a potential link between sleep-related erections and rapid eye movement sleep, which has implications for the current examination of sleep-related erections and further research into the mechanisms of erectile function. Meanwhile, the wearable device Fitbit has shown a potential promise for sleep monitoring in patients with erectile dysfunction. The results provide an alternative approach for further research on the relationship between erectile function and sleep with large sample sizes in the future.
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Affiliation(s)
- Guodong Liu
- Department of Urology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- Institute of Urology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- Anhui Province Key Laboratory of Genitourinary Diseases, Anhui Medical University, Hefei, Anhui, China
| | - Yuyang Zhang
- Department of Urology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- Institute of Urology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- Anhui Province Key Laboratory of Genitourinary Diseases, Anhui Medical University, Hefei, Anhui, China
| | - Wei Zhang
- Department of Urology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- Institute of Urology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- Anhui Province Key Laboratory of Genitourinary Diseases, Anhui Medical University, Hefei, Anhui, China
| | - Xu Wu
- Department of Urology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- Institute of Urology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- Anhui Province Key Laboratory of Genitourinary Diseases, Anhui Medical University, Hefei, Anhui, China
| | - Hui Jiang
- Department of Urology, Peking University First Hospital Institute of Urology, Peking University Andrology Center, Beijing, China
| | - Xiansheng Zhang
- Department of Urology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- Institute of Urology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- Anhui Province Key Laboratory of Genitourinary Diseases, Anhui Medical University, Hefei, Anhui, China
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Kawatani M, Itoi K, Talukder AH, Uchida K, Sakimura K, Kawatani M. Cholinergic modulation of CRH and non-CRH neurons in Barrington's nucleus of the mouse. J Neurophysiol 2020; 124:443-457. [PMID: 32609567 DOI: 10.1152/jn.00342.2019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Corticotropin-releasing hormone (CRH) is expressed in Barrington's nucleus (BarN), which plays an essential role in the regulation of micturition. To control the neural activities of BarN, glutamatergic and GABAergic inputs from multiple sources have been demonstrated; however, it is not clear how modulatory neurotransmitters affect the activity of BarN neurons. We have employed knock-in mice, CRH-expressing neurons of which are labeled with a modified yellow fluorescent protein (Venus). Using whole cell patch-clamp recordings, we examined the responses of Venus-expressing (putative CRH-expressing) neurons in BarN (BarCRH), as well as non-CRH-expressing neurons (BarCRH-negative), following bath application of cholinergic agonists. According to the present study, the activity of BarCRH neurons could be modulated by dual cholinergic mechanisms. First, they are inhibited by a muscarinic receptor-mediated mechanism, most likely through the M2 subclass of muscarinic receptors. Second, BarCRH neurons are excited by a nicotinic receptor-mediated mechanism. BarCRH-negative neurons also responded to cholinergic agents. Choline transporter-immunoreactive nerve terminals were observed in close proximity to the neurites, as well as the somata of BarCRH. The present results suggest that BarN neurons are capable of responding to cholinergic input.NEW & NOTEWORTHY This study investigates the effects of bath-applied cholinergic agonists on Barrington's nucleus (BarN) neurons in vitro. They were either excitatory, through nicotinic receptors, or inhibitory, through muscarinic receptors. Putative corticotropin-releasing hormone (CRH)-expressing neurons in BarN, as well as putative non-CRH-expressing neurons, responded to cholinergic agonists.
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Affiliation(s)
- Masahiro Kawatani
- Department of Neurophysiology, Graduate School of Medicine, Akita University, Akita, Japan
| | - Keiichi Itoi
- Laboratory of Information Biology, Graduate School of Information Sciences Tohoku University, Sendai, Japan.,Department of Neuroendocrinology, Graduate School of Medicine, Tohoku University, Sendai, Japan
| | - Ashraf Hossain Talukder
- Laboratory of Information Biology, Graduate School of Information Sciences Tohoku University, Sendai, Japan
| | - Katsuya Uchida
- Laboratory of Information Biology, Graduate School of Information Sciences Tohoku University, Sendai, Japan
| | - Kenji Sakimura
- Department of Cellular Neurobiology, Brain Research Institute, Niigata University, Niigata, Japan
| | - Masahito Kawatani
- Department of Neurophysiology, Graduate School of Medicine, Akita University, Akita, Japan
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Feng H, Wen SY, Qiao QC, Pang YJ, Wang SY, Li HY, Cai J, Zhang KX, Chen J, Hu ZA, Luo FL, Wang GZ, Yang N, Zhang J. Orexin signaling modulates synchronized excitation in the sublaterodorsal tegmental nucleus to stabilize REM sleep. Nat Commun 2020; 11:3661. [PMID: 32694504 PMCID: PMC7374574 DOI: 10.1038/s41467-020-17401-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 06/24/2020] [Indexed: 11/30/2022] Open
Abstract
The relationship between orexin/hypocretin and rapid eye movement (REM) sleep remains elusive. Here, we find that a proportion of orexin neurons project to the sublaterodorsal tegmental nucleus (SLD) and exhibit REM sleep-related activation. In SLD, orexin directly excites orexin receptor-positive neurons (occupying ~3/4 of total-population) and increases gap junction conductance among neurons. Their interaction spreads the orexin-elicited partial-excitation to activate SLD network globally. Besides, the activated SLD network exhibits increased probability of synchronized firings. This synchronized excitation promotes the correspondence between SLD and its downstream target to enhance SLD output. Using optogenetics and fiber-photometry, we consequently find that orexin-enhanced SLD output prolongs REM sleep episodes through consolidating brain state activation/muscle tone inhibition. After chemogenetic silencing of SLD orexin signaling, a ~17% reduction of REM sleep amounts and disruptions of REM sleep muscle atonia are observed. These findings reveal a stabilization role of orexin in REM sleep. Orexin signaling is provided by diffusely distributed fibers and involved in different brain circuits that orchestrate sleep and wakefulness states. Here, the authors show that a proportion of orexin neurons project to the sublaterodorsal tegmental nucleus and exhibit rapid eye movement (REM) sleep-related actions.
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Affiliation(s)
- Hui Feng
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Si-Yi Wen
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Qi-Cheng Qiao
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Yu-Jie Pang
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Sheng-Yun Wang
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Hao-Yi Li
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Jiao Cai
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Kai-Xuan Zhang
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Jing Chen
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Zhi-An Hu
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Fen-Lan Luo
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Guan-Zhong Wang
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Nian Yang
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China.
| | - Jun Zhang
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China.
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Carrera-Cañas C, Garzón M, de Andrés I. The Transition Between Slow-Wave Sleep and REM Sleep Constitutes an Independent Sleep Stage Organized by Cholinergic Mechanisms in the Rostrodorsal Pontine Tegmentum. Front Neurosci 2019; 13:748. [PMID: 31396036 PMCID: PMC6663996 DOI: 10.3389/fnins.2019.00748] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 07/05/2019] [Indexed: 12/11/2022] Open
Abstract
There is little information on either the transition state occurring between slow-wave sleep (SWS) and rapid eye movement (REM) sleep, as well as about its neurobiological bases. This transition state, which is known as the intermediate state (IS), is well-defined in rats but poorly characterized in cats. Previous studies in our laboratory demonstrated that cholinergic stimulation of the perilocus coeruleus α nucleus (PLCα) in the pontine tegmentum of cats induced two states: wakefulness with muscle atonia and a state of dissociated sleep we have called the SPGO state. The SPGO state has characteristics in common with the IS, such including the presence of ponto-geniculo-occipital waves (PGO) and EEG synchronization with δ wave reduction. Therefore, the aims of the present study were (1) to characterize the IS in the cat and, (2), to study the analogy between the SPGO and the different sleep stages showing PGO activity, including the IS. Polygraphic recordings of 10 cats were used. In seven cats carbachol microinjections (20-30 nL, 0.01-0.1 M) were delivered in the PLCα. In the different states, PGO waves were analyzed and power spectra obtained for the δ, θ, α, and β bands of the EEG from the frontal and occipital cortices, and for the θ hippocampal band. Statistical comparisons were made between the values obtained from the different states. The results indicate that the IS constitutes a state with characteristics that are distinct from both the preceding SWS and the following REM sleep, and that SPGO presents a high analogy with the IS. Therefore, the SPGO state induced by administering carbachol in the PLCα nucleus seems to be an expression of the physiological IS of the cat. Consequently, we propose that the PLCα region, besides being involved in the mechanisms of muscle atonia, may also be responsible for organizing the transition from SWS to REM sleep.
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Affiliation(s)
| | | | - Isabel de Andrés
- Departamento de Anatomía, Histología y Neurociencia, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
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Local and Relayed Effects of Deep Brain Stimulation of the Pedunculopontine Nucleus. Brain Sci 2019; 9:brainsci9030064. [PMID: 30889866 PMCID: PMC6468768 DOI: 10.3390/brainsci9030064] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 03/12/2019] [Accepted: 03/13/2019] [Indexed: 12/18/2022] Open
Abstract
Our discovery of low-threshold stimulation-induced locomotion in the pedunculopontine nucleus (PPN) led to the clinical use of deep brain stimulation (DBS) for the treatment of disorders such as Parkinson's disease (PD) that manifest gait and postural disorders. Three additional major discoveries on the properties of PPN neurons have opened new areas of research for the treatment of motor and arousal disorders. The description of (a) electrical coupling, (b) intrinsic gamma oscillations, and (c) gene regulation in the PPN has identified a number of novel therapeutic targets and methods for the treatment of a number of neurological and psychiatric disorders. We first delve into the circuit, cellular, intracellular, and molecular organization of the PPN, and then consider the clinical results to date on PPN DBS. This comprehensive review will provide valuable information to explain the network effects of PPN DBS, point to new directions for treatment, and highlight a number of issues related to PPN DBS.
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D'Onofrio S, Mahaffey S, Garcia-Rill E. Role of calcium channels in bipolar disorder. CURRENT PSYCHOPHARMACOLOGY 2017; 6:122-135. [PMID: 29354402 PMCID: PMC5771645 DOI: 10.2174/2211556006666171024141949] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Bipolar disorder is characterized by a host of sleep-wake abnormalities that suggests that the reticular activating system (RAS) is involved in these symptoms. One of the signs of the disease is a decrease in high frequency gamma band activity, which accounts for a number of additional deficits. Bipolar disorder has also been found to overexpress neuronal calcium sensor protein 1 (NCS-1). Recent studies showed that elements in the RAS generate gamma band activity that is mediated by high threshold calcium (Ca2+) channels. This mini-review provides a description of recent findings on the role of Ca2+ and Ca2+ channels in bipolar disorder, emphasizing the involvement of arousal-related systems in the manifestation of many of the disease symptoms. This will hopefully bring attention to a much-needed area of research and provide novel avenues for therapeutic development.
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Affiliation(s)
- Stasia D'Onofrio
- Center for Translational Neuroscience, University of Arkansas for Medical Sciences, Little Rock, AR
| | - Susan Mahaffey
- Center for Translational Neuroscience, University of Arkansas for Medical Sciences, Little Rock, AR
| | - Edgar Garcia-Rill
- Center for Translational Neuroscience, University of Arkansas for Medical Sciences, Little Rock, AR
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Urbano FJ, Luster BR, D'Onofrio S, Mahaffey S, Garcia-Rill E. Recording Gamma Band Oscillations in Pedunculopontine Nucleus Neurons. J Vis Exp 2016. [PMID: 27684729 DOI: 10.3791/54685] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Synaptic efferents from the PPN are known to modulate the neuronal activity of several intralaminar thalamic regions (e.g., the centrolateral/parafascicular; Cl/Pf nucleus). The activation of either the PPN or Cl/Pf nuclei in vivo has been described to induce the arousal of the animal and an increment in gamma band activity in the cortical electroencephalogram (EEG). The cellular mechanisms for the generation of gamma band oscillations in Reticular Activating System (RAS) neurons are the same as those found to generate gamma band oscillations in other brains nuclei. During current-clamp recordings of PPN neurons (from parasagittal slices from 9 - 25 day-old rats), the use of depolarizing square steps rapidly activated voltage-dependent potassium channels that prevented PPN neurons from being depolarized beyond -25 mV. Injecting 1 - 2 sec long depolarizing current ramps gradually depolarized PPN membrane potential resting values towards 0 mV. However, injecting depolarizing square pulses generated gamma-band oscillations of membrane potential that showed to be smaller in amplitude compared to the oscillations generated by ramps. All experiments were performed in the presence of voltage-gated sodium channels and fast synaptic receptors blockers. It has been shown that the activation of high-threshold voltage-dependent calcium channels underlie gamma-band oscillatory activity in PPN neurons. Specific methodological and pharmacological interventions are described here, providing the necessary tools to induce and sustain PPN subthreshold gamma band oscillation in vitro.
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Affiliation(s)
| | - Brennon R Luster
- Center for Translational Neuroscience, University of Arkansas for Medical Sciences
| | - Stasia D'Onofrio
- Center for Translational Neuroscience, University of Arkansas for Medical Sciences
| | - Susan Mahaffey
- Center for Translational Neuroscience, University of Arkansas for Medical Sciences
| | - Edgar Garcia-Rill
- Center for Translational Neuroscience, University of Arkansas for Medical Sciences;
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Monoaminergic control of brain states and sensory processing: Existing knowledge and recent insights obtained with optogenetics. Prog Neurobiol 2016; 151:237-253. [PMID: 27634227 DOI: 10.1016/j.pneurobio.2016.09.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 08/18/2016] [Accepted: 09/10/2016] [Indexed: 01/18/2023]
Abstract
Monoamines are key neuromodulators involved in a variety of physiological and pathological brain functions. Classical studies using physiological and pharmacological tools have revealed several essential aspects of monoaminergic involvement in regulating the sleep-wake cycle and influencing sensory responses but many features have remained elusive due to technical limitations. The application of optogenetic tools led to the ability of monitoring and controlling neuronal populations with unprecedented temporal precision and neurochemical specificity. Here, we focus on recent advances in revealing the roles of some monoamines in brain state control and sensory information processing. We summarize the central position of monoamines in integrating sensory processing across sleep-wake states with an emphasis on research conducted using optogenetic techniques. Finally, we discuss the limitations and perspectives of new integrated experimental approaches in understanding the modulatory mechanisms of monoaminergic systems in the mammalian brain.
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Arrigoni E, Chen MC, Fuller PM. The anatomical, cellular and synaptic basis of motor atonia during rapid eye movement sleep. J Physiol 2016; 594:5391-414. [PMID: 27060683 DOI: 10.1113/jp271324] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 03/02/2016] [Indexed: 01/14/2023] Open
Abstract
Rapid eye movement (REM) sleep is a recurring part of the sleep-wake cycle characterized by fast, desynchronized rhythms in the electroencephalogram (EEG), hippocampal theta activity, rapid eye movements, autonomic activation and loss of postural muscle tone (atonia). The brain circuitry governing REM sleep is located in the pontine and medullary brainstem and includes ascending and descending projections that regulate the EEG and motor components of REM sleep. The descending signal for postural muscle atonia during REM sleep is thought to originate from glutamatergic neurons of the sublaterodorsal nucleus (SLD), which in turn activate glycinergic pre-motor neurons in the spinal cord and/or ventromedial medulla to inhibit motor neurons. Despite work over the past two decades on many neurotransmitter systems that regulate the SLD, gaps remain in our knowledge of the synaptic basis by which SLD REM neurons are regulated and in turn produce REM sleep atonia. Elucidating the anatomical, cellular and synaptic basis of REM sleep atonia control is a critical step for treating many sleep-related disorders including obstructive sleep apnoea (apnea), REM sleep behaviour disorder (RBD) and narcolepsy with cataplexy.
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Affiliation(s)
- Elda Arrigoni
- Department of Neurology, Beth Israel Deaconess Medical Center, Division of Sleep Medicine, Harvard Medical School, Boston, MA, 02215, USA.
| | - Michael C Chen
- Department of Neurology, Beth Israel Deaconess Medical Center, Division of Sleep Medicine, Harvard Medical School, Boston, MA, 02215, USA
| | - Patrick M Fuller
- Department of Neurology, Beth Israel Deaconess Medical Center, Division of Sleep Medicine, Harvard Medical School, Boston, MA, 02215, USA.
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Garcia-Rill E, Luster B, D'Onofrio S, Mahaffey S, Bisagno V, Urbano FJ. Implications of gamma band activity in the pedunculopontine nucleus. J Neural Transm (Vienna) 2016; 123:655-665. [PMID: 26597124 PMCID: PMC4877293 DOI: 10.1007/s00702-015-1485-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 11/10/2015] [Indexed: 01/07/2023]
Abstract
The fact that the pedunculopontine nucleus (PPN) is part of the reticular activating system places it in a unique position to modulate sensory input and fight-or-flight responses. Arousing stimuli simultaneously activate ascending projections of the PPN to the intralaminar thalamus to trigger cortical high-frequency activity and arousal, as well as descending projections to reticulospinal systems to alter posture and locomotion. As such, the PPN has become a target for deep brain stimulation for the treatment of Parkinson's disease, modulating gait, posture, and higher functions. This article describes the latest discoveries on PPN physiology and the role of the PPN in a number of disorders. It has now been determined that high-frequency activity during waking and REM sleep is controlled by two different intracellular pathways and two calcium channels in PPN cells. Moreover, there are three different PPN cell types that have one or both calcium channels and may be active during waking only, REM sleep only, or both. Based on the new discoveries, novel mechanisms are proposed for insomnia as a waking disorder. In addition, neuronal calcium sensor protein-1 (NCS-1), which is over expressed in schizophrenia and bipolar disorder, may be responsible for the dysregulation in gamma band activity in at least some patients with these diseases. Recent results suggest that NCS-1 modulates PPN gamma band activity and that lithium acts to reduce the effects of over expressed NCS-1, accounting for its effectiveness in bipolar disorder.
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Affiliation(s)
- E Garcia-Rill
- Center for Translational Neuroscience, Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Slot 847, 4301 West Markham St., Little Rock, AR, 72205, USA.
| | - B Luster
- Center for Translational Neuroscience, Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Slot 847, 4301 West Markham St., Little Rock, AR, 72205, USA
| | - S D'Onofrio
- Center for Translational Neuroscience, Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Slot 847, 4301 West Markham St., Little Rock, AR, 72205, USA
| | - S Mahaffey
- Center for Translational Neuroscience, Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Slot 847, 4301 West Markham St., Little Rock, AR, 72205, USA
| | - V Bisagno
- IFIBYNE-CONICET, ININFA-CONICET, University of Buenos Aires, Buenos Aires, Argentina
| | - F J Urbano
- IFIBYNE-CONICET, ININFA-CONICET, University of Buenos Aires, Buenos Aires, Argentina
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Garcia-Rill E, D’Onofrio S, Luster B, Mahaffey S, Urbano FJ, Phillips C. The 10 Hz Frequency: A Fulcrum For Transitional Brain States. TRANSLATIONAL BRAIN RHYTHMICITY 2016; 1:7-13. [PMID: 27547831 PMCID: PMC4990355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
A 10 Hz rhythm is present in the occipital cortex when the eyes are closed (alpha waves), in the precentral cortex at rest (mu rhythm), in the superior and middle temporal lobe (tau rhythm), in the inferior olive (projection to cerebellar cortex), and in physiological tremor (underlying all voluntary movement). These are all considered resting rhythms in the waking brain which are "replaced" by higher frequency activity with sensorimotor stimulation. That is, the 10 Hz frequency fulcrum is replaced on the one hand by lower frequencies during sleep, or on the other hand by higher frequencies during volition and cognition. The 10 Hz frequency fulcrum is proposed as the natural frequency of the brain during quiet waking, but is replaced by higher frequencies capable of permitting more complex functions, or by lower frequencies during sleep and inactivity. At the center of the transition shifts to and from the resting rhythm is the reticular activating system, a phylogenetically preserved area of the brain essential for preconscious awareness.
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Affiliation(s)
- E. Garcia-Rill
- Center for Translational Neuroscience, University of Arkansas for Medical Sciences, Little Rock, AR, 72205, US
| | - S. D’Onofrio
- Center for Translational Neuroscience, University of Arkansas for Medical Sciences, Little Rock, AR, 72205, US
| | - B. Luster
- Center for Translational Neuroscience, University of Arkansas for Medical Sciences, Little Rock, AR, 72205, US
| | - S. Mahaffey
- Center for Translational Neuroscience, University of Arkansas for Medical Sciences, Little Rock, AR, 72205, US
| | - F. J. Urbano
- IFIBYNE-CONICET, University of Buenos Aires, Argentina
| | - C. Phillips
- Center for Translational Neuroscience, University of Arkansas for Medical Sciences, Little Rock, AR, 72205, US
- Department of Physical Therapy, Arkansas State University, Jonesboro, AR, 72401
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Black SW, Yamanaka A, Kilduff TS. Challenges in the development of therapeutics for narcolepsy. Prog Neurobiol 2015; 152:89-113. [PMID: 26721620 DOI: 10.1016/j.pneurobio.2015.12.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 11/14/2015] [Accepted: 12/04/2015] [Indexed: 01/19/2023]
Abstract
Narcolepsy is a neurological disorder that afflicts 1 in 2000 individuals and is characterized by excessive daytime sleepiness and cataplexy-a sudden loss of muscle tone triggered by positive emotions. Features of narcolepsy include dysregulation of arousal state boundaries as well as autonomic and metabolic disturbances. Disruption of neurotransmission through the hypocretin/orexin (Hcrt) system, usually by degeneration of the HCRT-producing neurons in the posterior hypothalamus, results in narcolepsy. The cause of Hcrt neurodegeneration is unknown but thought to be related to autoimmune processes. Current treatments for narcolepsy are symptomatic, including wake-promoting therapeutics that increase presynaptic dopamine release and anticataplectic agents that activate monoaminergic neurotransmission. Sodium oxybate is the only medication approved by the US Food and Drug Administration that alleviates both sleep/wake disturbances and cataplexy. Development of therapeutics for narcolepsy has been challenged by historical misunderstanding of the disease, its many disparate symptoms and, until recently, its unknown etiology. Animal models have been essential to elucidating the neuropathology underlying narcolepsy. These models have also aided understanding the neurobiology of the Hcrt system, mechanisms of cataplexy, and the pharmacology of narcolepsy medications. Transgenic rodent models will be critical in the development of novel therapeutics for the treatment of narcolepsy, particularly efforts directed to overcome challenges in the development of hypocretin replacement therapy.
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Affiliation(s)
- Sarah Wurts Black
- Center for Neuroscience, Biosciences Division, SRI International, Menlo Park, CA 94025, USA
| | - Akihiro Yamanaka
- Research Institute of Environmental Medicine, Nagoya University, Nagoya 464-8601, Japan
| | - Thomas S Kilduff
- Center for Neuroscience, Biosciences Division, SRI International, Menlo Park, CA 94025, USA.
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Abstract
Cortical electroencephalographic activity arises from corticothalamocortical interactions, modulated by wake-promoting monoaminergic and cholinergic input. These wake-promoting systems are regulated by hypothalamic hypocretin/orexins, while GABAergic sleep-promoting nuclei are found in the preoptic area, brainstem and lateral hypothalamus. Although pontine acetylcholine is critical for REM sleep, hypothalamic melanin-concentrating hormone/GABAergic cells may "gate" REM sleep. Daily sleep-wake rhythms arise from interactions between a hypothalamic circadian pacemaker and a sleep homeostat whose anatomical locus has yet to be conclusively defined. Control of sleep and wakefulness involves multiple systems, each of which presents vulnerability to sleep/wake dysfunction that may predispose to physical and/or neuropsychiatric disorders.
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Affiliation(s)
- Michael D Schwartz
- Biosciences Division, Center for Neuroscience, SRI International, 333 Ravenswood Avenue, Menlo Park, CA 94025, USA
| | - Thomas S Kilduff
- Biosciences Division, Center for Neuroscience, SRI International, 333 Ravenswood Avenue, Menlo Park, CA 94025, USA.
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Xi M, Fung SJ, Yamuy J, Chase MH. Interactions between hypocretinergic and GABAergic systems in the control of activity of neurons in the cat pontine reticular formation. Neuroscience 2015; 298:190-9. [PMID: 25892701 DOI: 10.1016/j.neuroscience.2015.04.022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 04/09/2015] [Accepted: 04/11/2015] [Indexed: 11/30/2022]
Abstract
Anatomical studies have demonstrated that hypocretinergic and GABAergic neurons innervate cells in the nucleus pontis oralis (NPO), a nucleus responsible for the generation of active (rapid eye movement (REM)) sleep (AS) and wakefulness (W). Behavioral and electrophysiological studies have shown that hypocretinergic and GABAergic processes in the NPO are involved in the generation of AS as well as W. An increase in hypocretin in the NPO is associated with both AS and W, whereas GABA levels in the NPO are elevated during W. We therefore examined the manner in which GABA modulates NPO neuronal responses to hypocretin. We hypothesized that interactions between the hypocretinergic and GABAergic systems in the NPO play an important role in determining the occurrence of AS or W. To determine the veracity of this hypothesis, we examined the effects of the juxtacellular application of hypocretin-1 and GABA on the activity of NPO neurons, which were recorded intracellularly, in chloralose-anesthetized cats. The juxtacellular application of hypocretin-1 significantly increased the mean amplitude of spontaneous EPSPs and the frequency of discharge of NPO neurons; in contrast, the juxtacellular microinjection of GABA produced the opposite effects, i.e., there was a significant reduction in the mean amplitude of spontaneous EPSPs and a decrease in the discharge of these cells. When hypocretin-1 and GABA were applied simultaneously, the inhibitory effect of GABA on the activity of NPO neurons was reduced or completely blocked. In addition, hypocretin-1 also blocked GABAergic inhibition of EPSPs evoked by stimulation of the laterodorsal tegmental nucleus. These data indicate that hypocretin and GABA function within the context of a neuronal gate that controls the activity of AS-on neurons. Therefore, we suggest that the occurrence of either AS or W depends upon interactions between hypocretinergic and GABAergic processes as well as inputs from other sites that project to AS-on neurons in the NPO.
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Affiliation(s)
- M Xi
- Websciences International, Los Angeles, CA 90024, USA; VA Greater Los Angeles Healthcare System, Los Angeles, CA 90073, USA.
| | - S J Fung
- Websciences International, Los Angeles, CA 90024, USA; VA Greater Los Angeles Healthcare System, Los Angeles, CA 90073, USA
| | - J Yamuy
- VA Greater Los Angeles Healthcare System, Los Angeles, CA 90073, USA; UCLA School of Medicine, Los Angeles, CA 90095, USA
| | - M H Chase
- Websciences International, Los Angeles, CA 90024, USA; VA Greater Los Angeles Healthcare System, Los Angeles, CA 90073, USA; UCLA School of Medicine, Los Angeles, CA 90095, USA
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15
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Boucetta S, Cissé Y, Mainville L, Morales M, Jones BE. Discharge profiles across the sleep-waking cycle of identified cholinergic, GABAergic, and glutamatergic neurons in the pontomesencephalic tegmentum of the rat. J Neurosci 2014; 34:4708-27. [PMID: 24672016 PMCID: PMC3965793 DOI: 10.1523/jneurosci.2617-13.2014] [Citation(s) in RCA: 196] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Revised: 02/19/2014] [Accepted: 02/22/2014] [Indexed: 01/04/2023] Open
Abstract
Distributed within the laterodorsal tegmental and pedunculopontine tegmental nuclei (LDT and PPT), cholinergic neurons in the pontomesencephalic tegmentum have long been thought to play a critical role in stimulating cortical activation during waking (W) and paradoxical sleep (PS, also called REM sleep), yet also in promoting PS with muscle atonia. However, the discharge profile and thus precise roles of the cholinergic neurons have remained uncertain because they lie intermingled with GABAergic and glutamatergic neurons, which might also assume these roles. By applying juxtacellular recording and labeling in naturally sleeping-waking, head-fixed rats, we investigated the discharge profiles of histochemically identified cholinergic, GABAergic, and glutamatergic neurons in the LDT, SubLDT, and adjoining medial part of the PPT (MPPT) in relation to sleep-wake states, cortical activity, and muscle tone. We found that all cholinergic neurons were maximally active during W and PS in positive correlation with fast (γ) cortical activity, as "W/PS-max active neurons." Like cholinergic neurons, many GABAergic and glutamatergic neurons were also "W/PS-max active." Other GABAergic and glutamatergic neurons were "PS-max active," being minimally active during W and maximally active during PS in negative correlation with muscle tone. Conversely, some glutamatergic neurons were "W-max active," being maximally active during W and minimally active during PS in positive correlation with muscle tone. Through different discharge profiles, the cholinergic, GABAergic, and glutamatergic neurons of the LDT, SubLDT, and MPPT thus appear to play distinct roles in promoting W and PS with cortical activation, PS with muscle atonia, or W with muscle tone.
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Affiliation(s)
- Soufiane Boucetta
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec H3A 2B4, Canada, and
| | - Youssouf Cissé
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec H3A 2B4, Canada, and
| | - Lynda Mainville
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec H3A 2B4, Canada, and
| | - Marisela Morales
- National Institute on Drug Abuse, Neuronal Networks Section, National Institutes of Health, Baltimore, Maryland 21224
| | - Barbara E. Jones
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec H3A 2B4, Canada, and
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Leonard CS, Kukkonen JP. Orexin/hypocretin receptor signalling: a functional perspective. Br J Pharmacol 2014; 171:294-313. [PMID: 23848055 PMCID: PMC3904253 DOI: 10.1111/bph.12296] [Citation(s) in RCA: 100] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Revised: 06/17/2013] [Accepted: 07/03/2013] [Indexed: 10/26/2022] Open
Abstract
Multiple homeostatic systems are regulated by orexin (hypocretin) peptides and their two known GPCRs. Activation of orexin receptors promotes waking and is essential for expression of normal sleep and waking behaviour, with the sleep disorder narcolepsy resulting from the absence of orexin signalling. Orexin receptors also influence systems regulating appetite/metabolism, stress and reward, and are found in several peripheral tissues. Nevertheless, much remains unknown about the signalling pathways and targets engaged by native receptors. In this review, we integrate knowledge about the orexin receptor signalling capabilities obtained from studies in expression systems and various native cell types (as presented in Kukkonen and Leonard, this issue of British Journal of Pharmacology) with knowledge of orexin signalling in different tissues. The tissues reviewed include the CNS, the gastrointestinal tract, the pituitary gland, pancreas, adrenal gland, adipose tissue and the male reproductive system. We also summarize the findings in different native and recombinant cell lines, especially focusing on the different cascades in CHO cells, which is the most investigated cell line. This reveals that while a substantial gap exists between what is known about orexin receptor signalling and effectors in recombinant systems and native systems, mounting evidence suggests that orexin receptor signalling is more diverse than originally thought. Moreover, rather than being restricted to orexin receptor 'overexpressing' cells, this signalling diversity may be utilized by native receptors in a site-specific manner.
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Affiliation(s)
- C S Leonard
- Department of Physiology, New York Medical College, Valhalla, NY, USA
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17
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Weng FJ, Williams RH, Hawryluk JM, Lu J, Scammell TE, Saper CB, Arrigoni E. Carbachol excites sublaterodorsal nucleus neurons projecting to the spinal cord. J Physiol 2013; 592:1601-17. [PMID: 24344163 DOI: 10.1113/jphysiol.2013.261800] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Considerable electrophysiological and pharmacological evidence has long suggested an important role for acetylcholine in the regulation of rapid-eye-movement (REM) sleep. For example, injection of the cholinergic agonist carbachol into the dorsomedial pons produces an REM sleep-like state with muscle atonia and cortical activation, both of which are cardinal features of REM sleep. Located within this region of the pons is the sublaterodorsal nucleus (SLD), a structure thought to be both necessary and sufficient for generating REM sleep muscle atonia. Subsets of glutamatergic SLD neurons potently contribute to motor inhibition during REM sleep through descending projections to motor-related glycinergic/GABAergic neurons in the spinal cord and ventromedial medulla. Prior electrophysiological and pharmacological studies examining the effects of acetylcholine on SLD neurons have, however, produced conflicting results. In the present study, we sought to clarify how acetylcholine influences the activity of spinally projecting SLD (SLDsp) neurons. We used retrograde tracing in combination with patch-clamp recordings and recorded pre- and postsynaptic effects of carbachol on SLDsp neurons. Carbachol acted presynaptically by increasing the frequency of glutamatergic miniature excitatory postsynaptic currents. We also found that carbachol directly excited SLDsp neurons by activating an Na(+)-Ca(2+) exchanger. Both pre- and postsynaptic effects were mediated by co-activation of M1 and M3 muscarinic receptors. These observations suggest that acetylcholine produces synergistic, excitatory pre- and postsynaptic responses on SLDsp neurons that, in turn, probably serve to promote muscle atonia during REM sleep.
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Affiliation(s)
- F J Weng
- Department of Neurology, Beth Israel Deaconess Medical Center, 3 Blackfan Circle, Center for Life Science Room 713, Boston, MA 02215, USA.
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18
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Yang N, Zhang KY, Wang FF, Hu ZA, Zhang J. Dopamine inhibits neurons from the rat dorsal subcoeruleus nucleus through the activation of α2-adrenergic receptors. Neurosci Lett 2013; 559:61-6. [PMID: 24304869 DOI: 10.1016/j.neulet.2013.11.037] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2013] [Revised: 11/20/2013] [Accepted: 11/21/2013] [Indexed: 10/25/2022]
Abstract
Previous studies have revealed that the central dopaminergic system may participate in regulating sleep/wakefulness. In particular, rapid eye movement (REM) sleep behavior disorder (RBD) occurs in patients with Parkinson's disease (PD), highlighting the possible connection between dopamine and REM sleep-related neural structures. The dorsal subcoeruleus nucleus (SubCD) is a critical structure for the generation and maintenance of REM sleep. Thus, the present study investigated the modulatory effects of dopamine on SubCD neurons. Using whole-cell patch clamp recordings, we first observed that dopamine induced a hyperpolarization of the membrane potentials in SubCD neurons and thus inhibited their firing. We determined that a dose-dependent and tetrodotoxin-resistant postsynaptic outward current underpinned this inhibitory effect on SubCD neurons induced by dopamine. Finally, using pharmacological agents, we revealed that the dopamine-elicited outward current in SubCD neurons was mediated by α2-adrenergic receptors, but not by the dopamine receptors, including D1-like and D2-like receptors. These results suggest that the central dopaminergic system may play a role in the regulation of REM sleep through the effect of dopamine on SubCD neurons. The relationship between the loss of this effect and the RBD in PD is discussed.
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Affiliation(s)
- Nian Yang
- Department of Physiology, Third Military Medical University, Chongqing 400038, PR China
| | - Kai-Yuan Zhang
- Student Brigade, Third Military Medical University, Chongqing 400038, PR China
| | - Fu-Fan Wang
- Student Brigade, Third Military Medical University, Chongqing 400038, PR China
| | - Zhi-An Hu
- Department of Physiology, Third Military Medical University, Chongqing 400038, PR China.
| | - Jun Zhang
- Department of Physiology, Third Military Medical University, Chongqing 400038, PR China.
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19
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McKenna JT, Yang C, Franciosi S, Winston S, Abarr KK, Rigby MS, Yanagawa Y, McCarley RW, Brown RE. Distribution and intrinsic membrane properties of basal forebrain GABAergic and parvalbumin neurons in the mouse. J Comp Neurol 2013; 521:1225-50. [PMID: 23254904 DOI: 10.1002/cne.23290] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Revised: 10/31/2012] [Accepted: 12/12/2012] [Indexed: 12/14/2022]
Abstract
The basal forebrain (BF) strongly regulates cortical activation, sleep homeostasis, and attention. Many BF neurons involved in these processes are GABAergic, including a subpopulation of projection neurons containing the calcium-binding protein, parvalbumin (PV). However, technical difficulties in identification have prevented a precise mapping of the distribution of GABAergic and GABA/PV+ neurons in the mouse or a determination of their intrinsic membrane properties. Here we used mice expressing fluorescent proteins in GABAergic (GAD67-GFP knock-in mice) or PV+ neurons (PV-Tomato mice) to study these neurons. Immunohistochemical staining for GABA in GAD67-GFP mice confirmed that GFP selectively labeled BF GABAergic neurons. GFP+ neurons and fibers were distributed throughout the BF, with the highest density in the magnocellular preoptic area (MCPO). Immunohistochemistry for PV indicated that the majority of PV+ neurons in the BF were large (>20 μm) or medium-sized (15-20 μm) GFP+ neurons. Most medium and large-sized BF GFP+ neurons, including those retrogradely labeled from the neocortex, were fast-firing and spontaneously active in vitro. They exhibited prominent hyperpolarization-activated inward currents and subthreshold "spikelets," suggestive of electrical coupling. PV+ neurons recorded in PV-Tomato mice had similar properties but had significantly narrower action potentials and a higher maximal firing frequency. Another population of smaller GFP+ neurons had properties similar to striatal projection neurons. The fast firing and electrical coupling of BF GABA/PV+ neurons, together with their projections to cortical interneurons and the thalamic reticular nucleus, suggest a strong and synchronous control of the neocortical fast rhythms typical of wakefulness and REM sleep.
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Affiliation(s)
- James T McKenna
- Laboratory of Neuroscience, VA Boston Healthcare System and Harvard Medical School, Department of Psychiatry, Brockton, Massachusetts, 02301, USA
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20
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Xi M, Fung SJ, Zhang J, Sampogna S, Chase MH. The amygdala and the pedunculopontine tegmental nucleus: Interactions controlling active (rapid eye movement) sleep. Exp Neurol 2012; 238:44-51. [DOI: 10.1016/j.expneurol.2012.08.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Revised: 07/23/2012] [Accepted: 08/01/2012] [Indexed: 11/28/2022]
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21
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Garcia-Rill E, Kezunovic N, Hyde J, Simon C, Beck P, Urbano FJ. Coherence and frequency in the reticular activating system (RAS). Sleep Med Rev 2012; 17:227-38. [PMID: 23044219 DOI: 10.1016/j.smrv.2012.06.002] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Revised: 05/17/2012] [Accepted: 06/07/2012] [Indexed: 12/24/2022]
Abstract
This review considers recent evidence showing that cells in the reticular activating system (RAS) exhibit (1) electrical coupling mainly in GABAergic cells, and (2) gamma band activity in virtually all of the cells. Specifically, cells in the mesopontine pedunculopontine nucleus (PPN), intralaminar parafascicular nucleus (Pf), and pontine dorsal subcoeruleus nucleus dorsalis (SubCD) (1) show electrical coupling, and (2) all fire in the beta/gamma band range when maximally activated, but no higher. The mechanism behind electrical coupling is important because the stimulant modafinil was shown to increase electrical coupling. We also provide recent findings demonstrating that all cells in the PPN and Pf have high threshold, voltage-dependent P/Q-type calcium channels that are essential to gamma band activity. On the other hand, all SubCD, and some PPN, cells manifested sodium-dependent subthreshold oscillations. A novel mechanism for sleep-wake control based on transmitter interactions, electrical coupling, and gamma band activity is described. We speculate that continuous sensory input will modulate coupling and induce gamma band activity in the RAS that could participate in the processes of preconscious awareness, and provide the essential stream of information for the formulation of many of our actions.
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Affiliation(s)
- Edgar Garcia-Rill
- Center for Translational Neuroscience, Department of Neurobiology & Dev. Sci., University of Arkansas for Medical Sciences, 4301 West Markham St., Slot 847, Little Rock, AR 72205, USA.
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22
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Abstract
This review summarizes the brain mechanisms controlling sleep and wakefulness. Wakefulness promoting systems cause low-voltage, fast activity in the electroencephalogram (EEG). Multiple interacting neurotransmitter systems in the brain stem, hypothalamus, and basal forebrain converge onto common effector systems in the thalamus and cortex. Sleep results from the inhibition of wake-promoting systems by homeostatic sleep factors such as adenosine and nitric oxide and GABAergic neurons in the preoptic area of the hypothalamus, resulting in large-amplitude, slow EEG oscillations. Local, activity-dependent factors modulate the amplitude and frequency of cortical slow oscillations. Non-rapid-eye-movement (NREM) sleep results in conservation of brain energy and facilitates memory consolidation through the modulation of synaptic weights. Rapid-eye-movement (REM) sleep results from the interaction of brain stem cholinergic, aminergic, and GABAergic neurons which control the activity of glutamatergic reticular formation neurons leading to REM sleep phenomena such as muscle atonia, REMs, dreaming, and cortical activation. Strong activation of limbic regions during REM sleep suggests a role in regulation of emotion. Genetic studies suggest that brain mechanisms controlling waking and NREM sleep are strongly conserved throughout evolution, underscoring their enormous importance for brain function. Sleep disruption interferes with the normal restorative functions of NREM and REM sleep, resulting in disruptions of breathing and cardiovascular function, changes in emotional reactivity, and cognitive impairments in attention, memory, and decision making.
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Affiliation(s)
- Ritchie E Brown
- Laboratory of Neuroscience, VA Boston Healthcare System and Harvard Medical School, Brockton, Massachusetts 02301, USA
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23
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Lungwitz EA, Molosh A, Johnson PL, Harvey BP, Dirks RC, Dietrich A, Minick P, Shekhar A, Truitt WA. Orexin-A induces anxiety-like behavior through interactions with glutamatergic receptors in the bed nucleus of the stria terminalis of rats. Physiol Behav 2012; 107:726-32. [PMID: 22652097 DOI: 10.1016/j.physbeh.2012.05.019] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Revised: 05/22/2012] [Accepted: 05/23/2012] [Indexed: 12/22/2022]
Abstract
The hypothalamic neuropeptide orexin (ORX) has been implicated in anxiety, and anxiety-like behaviors. The purpose of these studies was to determine the role of ORX, specifically orexin-A (ORX-A) in the bed nucleus of the stria terminalis (BNST) on anxiety-like behaviors in rats. Rats injected with ORX-A into the BNST displayed greater anxiety-like measures in the social interaction and elevated plus maze tests compared to vehicle treated controls. Such anxiety-like behaviors were not observed when the ORX-A injections were adjacent to the BNST, in the medial septum. The anxiety-inducing effects of direct infusions of ORX-A into the BNST may be a consequence of increased activation of BNST neurons. In BNST slice preparations using patch-clamp techniques, ORX-A induced membrane depolarization and generation of action potentials in a subset of BNST neurons. The anxiety-inducing effects of ORX-A in the BNST also appear to be dependent on NMDA-type glutamate receptor activity, as pre-injecting the NMDA antagonist AP5 into the BNST blocked anxiogenic effects of local ORX-A injections. Injections of AMPA-type receptor antagonists into the BNST prior to ORX-A resulted in only a partial attenuation of anxiety-like behaviors.
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Affiliation(s)
- Elizabeth A Lungwitz
- Graduate Program in Medical Neuroscience, Indiana Clinical and Translational Sciences Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA
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24
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Simon C, Hayar A, Garcia-Rill E. Developmental changes in glutamatergic fast synaptic neurotransmission in the dorsal subcoeruleus nucleus. Sleep 2012; 35:407-17. [PMID: 22379247 DOI: 10.5665/sleep.1706] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
STUDY OBJECTIVES The dorsal subcoeruleus nucleus (SubCD) is involved in the generation of rapid eye movement sleep (REM), a state distinguished by high-frequency EEG activity, muscle atonia, and ponto-geniculo-occipital (PGO) waves. Activation of the SubCD by injection of the glutamate (GLU) receptor agonist kainic acid (KA) produced a REM sleep-like state with muscle atonia. We tested the hypothesis that developmental changes in the GLU excitability of SubCD neurons could underlie the developmental decrease in REM sleep that occurs in the rat from postnatal days 10-30. DESIGN Sagittal sections containing the SubCD were cut using 9-15 day old rat pups. Whole-cell patch clamp recordings were performed on SubCD neurons and responses were measured following electrical stimulation or bath application of the GLU receptor agonists N-methyl-D-aspartic acid (NMDA) or KA. MEASUREMENTS AND RESULTS Pharmacological or electrical stimulation increased non-cholinergic excitatory postsynaptic currents (EPSCs) in SubCD neurons, which were blocked by GLU receptor antagonists. Although no developmental changes were observed in the relative contribution of AMPA/KA and NMDA receptors to the responses, there was a developmental decrease in the half-width duration of both evoked and miniature EPSCs. Bath application of NMDA or KA revealed a developmental decrease in the direct response of SubCD neurons to these agonists. CONCLUSIONS The SubCD receives glutamatergic input, which may be involved in activation of SubCD neurons during REM sleep. A developmental decrease in the glutamatergic excitability of these neurons could underlie the developmental decrease in REM sleep observed in humans and rodents.
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Affiliation(s)
- Christen Simon
- Center for Translational Neuroscience, Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
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25
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Urbano FJ, Kezunovic N, Hyde J, Simon C, Beck P, Garcia-Rill E. Gamma band activity in the reticular activating system. Front Neurol 2012; 3:6. [PMID: 22319508 PMCID: PMC3269033 DOI: 10.3389/fneur.2012.00006] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2011] [Accepted: 01/06/2012] [Indexed: 12/24/2022] Open
Abstract
This review considers recent evidence showing that cells in three regions of the reticular activating system (RAS) exhibit gamma band activity, and describes the mechanisms behind such manifestation. Specifically, we discuss how cells in the mesopontine pedunculopontine nucleus (PPN), intralaminar parafascicular nucleus (Pf), and pontine subcoeruleus nucleus dorsalis (SubCD) all fire in the beta/gamma band range when maximally activated, but no higher. The mechanisms behind this ceiling effect have been recently elucidated. We describe recent findings showing that every cell in the PPN have high-threshold, voltage-dependent P/Q-type calcium channels that are essential, while N-type calcium channels are permissive, to gamma band activity. Every cell in the Pf also showed that P/Q-type and N-type calcium channels are responsible for this activity. On the other hand, every SubCD cell exhibited sodium-dependent subthreshold oscillations. A novel mechanism for sleep–wake control based on well-known transmitter interactions, electrical coupling, and gamma band activity is described. The data presented here on inherent gamma band activity demonstrates the global nature of sleep–wake oscillation that is orchestrated by brainstem–thalamic mechanism, and questions the undue importance given to the hypothalamus for regulation of sleep–wakefulness. The discovery of gamma band activity in the RAS follows recent reports of such activity in other subcortical regions like the hippocampus and cerebellum. We hypothesize that, rather than participating in the temporal binding of sensory events as seen in the cortex, gamma band activity manifested in the RAS may help stabilize coherence related to arousal, providing a stable activation state during waking and paradoxical sleep. Most of our thoughts and actions are driven by pre-conscious processes. We speculate that continuous sensory input will induce gamma band activity in the RAS that could participate in the processes of pre-conscious awareness, and provide the essential stream of information for the formulation of many of our actions.
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Affiliation(s)
- Francisco J Urbano
- Instituto de Fisiología, Biología Molecular y Neurociencias, Consejo Nacional de Investigaciones Científicas y Técnicas, University of Buenos Aires Buenos Aires, Argentina
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26
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Xi M, Fung SJ, Sampogna S, Chase MH. Excitatory projections from the amygdala to neurons in the nucleus pontis oralis in the rat: an intracellular study. Neuroscience 2011; 197:181-90. [PMID: 21955600 DOI: 10.1016/j.neuroscience.2011.09.029] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Revised: 08/25/2011] [Accepted: 09/11/2011] [Indexed: 11/20/2022]
Abstract
There is a consensus that active (REM) sleep (AS) is controlled by cholinergic projections from the laterodorsal and pedunculopontine tegmental nuclei (LDT/PPT) to neurons in the nucleus pontis oralis (NPO) that generate AS (i.e. AS-Generator neurons). The present study was designed to provide evidence that other projections to the NPO, such as those from the amygdala, are also capable of inducing AS. Accordingly, the responses of neurons, recorded intracellularly in the NPO, were examined following stimulation of the ipsilateral central nucleus of the amygdala (CNA) in urethane-anesthetized rats. Single pulse stimulation in the CNA produced an early, fast depolarizing potential (EPSP) in neurons within the NPO. The mean latency to the onset of these excitatory postsynaptic potentials (EPSPs) was 3.6±0.2 ms. A late, small-amplitude inhibitory synaptic potential (IPSP) was present following EPSPs in a portion of the NPO neurons. Following stimulation of the CNA with a train of 8-10 pulses, NPO neurons exhibited a sustained depolarization (5-10 mV) of their resting membrane potential. When single subthreshold intracellular depolarizing current pulses were delivered to NPO neurons, CNA-induced EPSPs were sufficient to promote the discharge of these cells. Stimulation of the CNA with a short train of stimuli induced potent temporal facilitation of EPSPs in NPO neurons. Two forms of synaptic plasticity were revealed by the patterns of response of NPO neurons following stimulation of the CNA: paired-pulse facilitation (PPF) and post-tetanic potentiation (PTP). Six of recorded NPO neurons were identified morphologically with neurobiotin. They were medium to large, multipolar cells with diameters >20 μM, which resemble AS-on cells in the NPO. The present results demonstrate that amygdalar projections are capable of exerting a powerful excitatory postsynaptic drive that activates NPO neurons. Therefore, we suggest that the amygdala is capable of inducing AS via direct projections to AS-Generator neurons in the NPO.
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Affiliation(s)
- M Xi
- WebSciences International, Los Angeles, CA 90024, USA.
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27
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Simon C, Kezunovic N, Williams DK, Urbano FJ, Garcia-Rill E. Cholinergic and glutamatergic agonists induce gamma frequency activity in dorsal subcoeruleus nucleus neurons. Am J Physiol Cell Physiol 2011; 301:C327-35. [PMID: 21543743 DOI: 10.1152/ajpcell.00093.2011] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The dorsal subcoeruleus nucleus (SubCD) is involved in generating two signs of rapid eye movement (REM) sleep: muscle atonia and ponto-geniculo-occipital (PGO) waves. We tested the hypothesis that single cell and/or population responses of SubCD neurons are capable of generating gamma frequency activity in response to intracellular stimulation or receptor agonist activation. Whole cell patch clamp recordings (immersion chamber) and population responses (interface chamber) were conducted on 9- to 20-day-old rat brain stem slices. All SubCD neurons (n = 103) fired at gamma frequency when subjected to depolarizing steps. Two statistically distinct populations of neurons were observed, which were distinguished by their high (>80 Hz, n = 24) versus low (35-80 Hz, n = 16) initial firing frequencies. Both cell types exhibited subthreshold oscillations in the gamma range (n = 43), which may underlie the gamma band firing properties of these neurons. The subthreshold oscillations were blocked by the sodium channel blockers tetrodotoxin (TTX, n = 21) extracellularly and N-(2,6-dimethylphenylcarbamoylmethyl)triethylammonium bromide (QX-314) intracellularly (n = 5), indicating they were sodium channel dependent. Gamma frequency subthreshold oscillations were observed in response to the nonspecific cholinergic receptor agonist carbachol (CAR, n = 11, d = 1.08) and the glutamate receptor agonists N-methyl-d-aspartic acid (NMDA, n = 12, d = 1.09) and kainic acid (KA, n = 13, d = 0.96), indicating that cholinergic and glutamatergic inputs may be involved in the activation of these subthreshold currents. Gamma band activity also was observed in population responses following application of CAR (n = 4, P < 0.05), NMDA (n = 4, P < 0.05) and KA (n = 4, P < 0.05). Voltage-sensitive, sodium channel-dependent gamma band activity appears to be a part of the intrinsic membrane properties of SubCD neurons.
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Affiliation(s)
- Christen Simon
- Center for Translational Neuroscience, Department of Neurobiology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
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Nuñez A, Rodrigo-Angulo ML, Andrés ID, Garzón M. Hypocretin/Orexin neuropeptides: participation in the control of sleep-wakefulness cycle and energy homeostasis. Curr Neuropharmacol 2010; 7:50-9. [PMID: 19721817 PMCID: PMC2724663 DOI: 10.2174/157015909787602797] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2008] [Revised: 08/19/2008] [Accepted: 09/17/2008] [Indexed: 11/28/2022] Open
Abstract
Hypocretins or orexins (Hcrt/Orx) are hypothalamic neuropeptides that are synthesized by neurons located mainly in the perifornical area of the posterolateral hypothalamus. These hypothalamic neurons are the origin of an extensive and divergent projection system innervating numerous structures of the central nervous system. In recent years it has become clear that these neuropeptides are involved in the regulation of many organic functions, such as feeding, thermoregulation and neuroendocrine and cardiovascular control, as well as in the control of the sleep-wakefulness cycle. In this respect, Hcrt/Orx activate two subtypes of G protein-coupled receptors (Hcrt/Orx1R and Hcrt/Orx2R) that show a partly segregated and prominent distribution in neural structures involved in sleep-wakefulness regulation. Wakefulness-enhancing and/or sleep-suppressing actions of Hcrt/Orx have been reported in specific areas of the brainstem. Moreover, presently there are animal models of human narcolepsy consisting in modifications of Hcrt/Orx receptors or absence of these peptides. This strongly suggests that narcolepsy is the direct consequence of a hypofunction of the Hcrt/Orx system, which is most likely due to Hcrt/Orx neurons degeneration. The main focus of this review is to update and illustrate the available data on the actions of Hcrt/Orx neuropeptides with special interest in their participation in the control of the sleep-wakefulness cycle and the regulation of energy homeostasis. Current pharmacological treatment of narcolepsy is also discussed.
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Affiliation(s)
- A Nuñez
- Departamento de Anatomía, Histología y Neurociencia, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.
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Simon C, Kezunovic N, Ye M, Hyde J, Hayar A, Williams DK, Garcia-Rill E. Gamma band unit activity and population responses in the pedunculopontine nucleus. J Neurophysiol 2010; 104:463-74. [PMID: 20463196 DOI: 10.1152/jn.00242.2010] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
The pedunculopontine nucleus (PPN) is involved in the activated states of waking and paradoxical sleep, forming part of the reticular activating system (RAS). The studies described tested the hypothesis that single unit and/or population responses of PPN neurons are capable of generating gamma band frequency activity. Whole cell patch clamp recordings (immersion chamber) and population responses (interface chamber) were conducted on 9- to 20-day-old rat brain stem slices. Regardless of cell type (I, II, or III) or type of response to the nonselective cholinergic receptor agonist carbachol (excitation, inhibition, biphasic), almost all PPN neurons fired at gamma band frequency, but no higher, when subjected to depolarizing steps (50 +/- 2 Hz, mean +/- SE). Nonaccommodating neurons fired at 18-100 Hz throughout depolarizing steps, while most accommodating neurons exhibited gamma band frequency of action potentials followed by gamma band membrane oscillations. These oscillations were blocked by the sodium channel blocker tetrodotoxin (TTX), suggesting that at least some are mediated by sodium currents. Population responses in the PPN showed that carbachol induced peaks of activation in the theta and gamma range, while glutamatergic receptor agonists induced overall increases in activity at theta and gamma frequencies, although in differing patterns. Gamma band activity appears to be a part of the intrinsic membrane properties of PPN neurons, and the population as a whole generates different patterns of gamma band activity under the influence of specific transmitters. Given sufficient excitation, the PPN may impart gamma band activation on its targets.
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Affiliation(s)
- Christen Simon
- Center for Translational Neuroscience, Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA
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Diniz Behn CG, Booth V. Simulating Microinjection Experiments in a Novel Model of the Rat Sleep-Wake Regulatory Network. J Neurophysiol 2010; 103:1937-53. [DOI: 10.1152/jn.00795.2009] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
This study presents a novel mathematical modeling framework that is uniquely suited to investigating the structure and dynamics of the sleep-wake regulatory network in the brain stem and hypothalamus. It is based on a population firing rate model formalism that is modified to explicitly include concentration levels of neurotransmitters released to postsynaptic populations. Using this framework, interactions among primary brain stem and hypothalamic neuronal nuclei involved in rat sleep-wake regulation are modeled. The model network captures realistic rat polyphasic sleep-wake behavior consisting of wake, rapid eye movement (REM) sleep, and non-REM (NREM) sleep states. Network dynamics include a cyclic pattern of NREM sleep, REM sleep, and wake states that is disrupted by simulated variability of neurotransmitter release and external noise to the network. Explicit modeling of neurotransmitter concentrations allows for simulations of microinjections of neurotransmitter agonists and antagonists into a key wake-promoting population, the locus coeruleus (LC). Effects of these simulated microinjections on sleep-wake states are tracked and compared with experimental observations. Agonist/antagonist pairs, which are presumed to have opposing effects on LC activity, do not generally induce opposing effects on sleep-wake patterning because of multiple mechanisms for LC activation in the network. Also, different agents, which are presumed to have parallel effects on LC activity, do not induce parallel effects on sleep-wake patterning because of differences in the state dependence or independence of agonist and antagonist action. These simulation results highlight the utility of formal mathematical modeling for constraining conceptual models of the sleep-wake regulatory network.
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Affiliation(s)
| | - Victoria Booth
- Departments of Mathematics and
- Anesthesiology, University of Michigan, Ann Arbor, Michigan
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Tartar JL, McKenna JT, Ward CP, McCarley RW, Strecker RE, Brown RE. Sleep fragmentation reduces hippocampal CA1 pyramidal cell excitability and response to adenosine. Neurosci Lett 2009; 469:1-5. [PMID: 19914331 DOI: 10.1016/j.neulet.2009.11.032] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2009] [Revised: 10/22/2009] [Accepted: 11/09/2009] [Indexed: 11/29/2022]
Abstract
Sleep fragmentation (SF) impairs the restorative/cognitive benefits of sleep via as yet unidentified alterations in neural physiology. Previously, we found that hippocampal synaptic plasticity and spatial learning are impaired in a rat model of SF which utilizes a treadmill to awaken the animals every 2 min, mimicking the frequency of awakenings observed in human sleep apnea patients. Here, we investigated the cellular mechanisms responsible for these effects, using whole-cell patch-clamp recordings. 24h of SF decreased the excitability of hippocampal CA1 pyramidal neurons via decreased input resistance, without alterations in other intrinsic membrane or action potential properties (when compared to cage controls, or to exercise controls that experienced the same total amount of treadmill movement as SF rats). Contrary to our initial prediction, the hyperpolarizing response to bath applied adenosine (30 microM) was reduced in the CA1 neurons of SF treated rats. Our initial prediction was based on the evidence that sleep loss upregulates cortical adenosine A1 receptors; however, the present findings are consistent with a very recent report that hippocampal A1 receptors are not elevated by sleep loss. Thus, increased adenosinergic inhibition is unlikely to be responsible for reduced hippocampal long-term potentiation in SF rats. Instead, the reduced excitability of CA1 pyramidal neurons observed here may contribute to the loss of hippocampal long-term potentiation and hippocampus-dependent cognitive impairments associated with sleep disruption.
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Affiliation(s)
- Jaime L Tartar
- VA Boston Healthcare System and Harvard Medical School, Research 151-C, 940 Belmont Street, Brockton, MA 02301, USA
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Affiliation(s)
- Subimal Datta
- Laboratory of Sleep and Cognitive Neuroscience, Department of Psychiatry, Boston University School of Medicine, Boston, MA, USA.
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Heister DS, Hayar A, Garcia-Rill E. Cholinergic modulation of GABAergic and glutamatergic transmission in the dorsal subcoeruleus: mechanisms for REM sleep control. Sleep 2009; 32:1135-47. [PMID: 19750918 PMCID: PMC2737571 DOI: 10.1093/sleep/32.9.1135] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
STUDY OBJECTIVES Dorsal subcoeruleus (SubCD) neurons are thought to promote PGO waves and to be modulated by cholinergic afferents during REM sleep. We examined the differential effect of the cholinergic agonist carbachol (CAR) on excitatory and inhibitory postsynaptic currents (PSCs), and investigated the effects of CAR on SubCD neurons during the developmental decrease in REM sleep. DESIGN Whole-cell patch clamp recordings were conducted on brainstem slices of 7- to 20-day-old rats. MEASUREMENTS AND RESULTS CAR acted directly on 50% of SubCD neurons by inducing an inward current, via both nicotinic and muscarinic M1 receptors. CAR induced a potassium mediated outward current via activation of M2 muscarinic receptors in 43% of SubCD cells. Evoked stimulation established the presence of NMDA, AMPA, GABA, and glycinergic PSCs in the SubCD. CAR was found to decrease the amplitude of evoked EPSCs in 31 of 34 SubCD cells, but decreased the amplitude of evoked IPSCs in only 1 of 13 SubCD cells tested. Spontaneous EPSCs were decreased by CAR in 55% of cells recorded, while spontaneous IPSCs were increased in 27% of SubCD cells. These findings indicate that CAR exerts a predominantly inhibitory role on fast synaptic glutamatergic activity and a predominantly excitatory role on fast synaptic GABAergic/glycinergic activity in the SubCD. CONCLUSION We hypothesize that during REM sleep, cholinergic "REM-on" neurons that project to the SubCD induce an excitation of inhibitory interneurons and inhibition of excitatory events leading to the production of coordinated activity in SubCD projection neurons. The coordination of these projection neurons may be essential for the production of REM sleep signs such as PGO waves.
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Affiliation(s)
- David S. Heister
- Center for Translational Neuroscience, Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR
| | - Abdallah Hayar
- Center for Translational Neuroscience, Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR
| | - Edgar Garcia-Rill
- Center for Translational Neuroscience, Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR
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Volgin DV, Malinowska M, Kubin L. Dorsomedial pontine neurons with descending projections to the medullary reticular formation express orexin-1 and adrenergic alpha2A receptor mRNA. Neurosci Lett 2009; 459:115-8. [PMID: 19427365 DOI: 10.1016/j.neulet.2009.05.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2009] [Revised: 05/02/2009] [Accepted: 05/05/2009] [Indexed: 01/13/2023]
Abstract
Neurons located in the dorsomedial pontine rapid eye movement (REM) sleep-triggering region send axons to the medial medullary reticular formation (mMRF). This pathway is believed to be important for the generation of REM sleep motor atonia, but other than that they are glutamatergic little is known about neurochemical signatures of these pontine neurons important for REM sleep. We used single-cell reverse transcription and polymerase chain reaction (RT-PCR) to determine whether dorsomedial pontine cells with projections to the mMRF express mRNA for selected membrane receptors that mediate modulatory influences on REM sleep. Fluorescein (FITC)-labeled latex microspheres were microinjected into the mMRF of 26-34-day-old rats under pentobarbital anesthesia. After 5-6 days, rats were sacrificed, pontine slices were obtained and neurons were dissociated from 400 to 600 microm micropunches extracted from dorsomedial pontine reticular formation. We found that 32 out of 51 FITC-labeled cells tested (63+/-7% (SE)) contained the orexin type 1 receptor (ORX1r) mRNA, 27 out of 73 (37+/-6%) contained the adrenergic alpha(2A) receptor (alpha(2A)r) RNA, and 6 out of 31 (19+/-7%) contained both mRNAs. The percentage of cells positive for the ORX1r mRNA was significantly lower (p<0.04) for the dorsomedial pontine cells that were not retrogradely labeled from the mMRF (32+/-11%), whereas alpha(2A)r mRNA was present in a similar percentage of FITC-labeled and unlabeled neurons. Our data suggest that ORX and adrenergic pathways converge on a subpopulation of cells of the pontine REM sleep-triggering region that have descending projections to the medullary region important for the motor control during REM sleep.
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Affiliation(s)
- Denys V Volgin
- Department of Animal Biology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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Ertan AA, Çelebi N, Bayolken M, Onur MA, Aboushelib MN, Feilzer A, Cehreli M. Surface topography of zirconia implants does not alter action potentials of isolated rat sciatic nerves. J Biomed Mater Res B Appl Biomater 2009; 88:182-90. [DOI: 10.1002/jbm.b.31166] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Brischoux F, Mainville L, Jones BE. Muscarinic-2 and orexin-2 receptors on GABAergic and other neurons in the rat mesopontine tegmentum and their potential role in sleep-wake state control. J Comp Neurol 2008; 510:607-30. [DOI: 10.1002/cne.21803] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Rukhadze I, Fenik VB, Branconi JL, Kubin L. Fos expression in pontomedullary catecholaminergic cells following rapid eye movement sleep-like episodes elicited by pontine carbachol in urethane-anesthetized rats. Neuroscience 2008; 152:208-22. [PMID: 18155849 DOI: 10.1016/j.neuroscience.2007.11.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2007] [Revised: 11/09/2007] [Accepted: 11/09/2007] [Indexed: 02/07/2023]
Abstract
Pontine noradrenergic neurons of the locus coeruleus (LC) and sub-coeruleus (SubC) region cease firing during rapid eye movement sleep (REMS). This plays a permissive role in the generation of REMS and may contribute to state-dependent modulation of transmission in the CNS. Whether all pontomedullary catecholaminergic neurons, including those in the A1/C1, A2/C2 and A7 groups, have REMS-related suppression of activity has not been tested. We used Fos protein expression as an indirect marker of the level of neuronal activity and linear regression analysis to determine whether pontomedullary cells identified by tyrosine hydroxylase (TH) immunohistochemistry have reduced Fos expression following REMS-like state induced by pontine microinjections of a cholinergic agonist, carbachol in urethane-anesthetized rats. The percentage of Fos-positive TH cells was negatively correlated with the cumulative duration of REMS-like episodes induced during 140 min prior to brain harvesting in the A7 and rostral A5 groups bilaterally (P < 0.01 for both), and in SubC neurons on the side opposite to carbachol injection (P < 0.05). Dorsal medullary A2/C2 neurons did not exhibit such correlation, but their Fos expression (and that in A7, rostral A5 and SubC neurons) was positively correlated with the duration of the interval between the last REMS-like episode and the time of perfusion (P < 0.05). In contrast, neither of these correlations was significant for A1 /C1 or caudal A5 neurons. These findings suggest that, similar to the prototypic LC neurons, neurons of the A7, rostral A5 and A2/C2 groups have reduced or abolished activity during REMS, whereas A1 /IC1 and caudal A5 neurons do not have this feature. The reduced activity of A2/C2, A5 and A7 neurons during REMS, and the associated decrements in norepinephrine release, may cause state-dependent modulation of.transmission in brain somato- and viscerosensory, somatomotor, and cardiorespiratory pathways.
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Affiliation(s)
- I Rukhadze
- Department of Animal Biology 209E/VET, School of Veterinary Medicine and Center for Sleep and Respiratory Neurobiology, University of Pennsylvania, 3800 Spruce Street, Philadelphia, PA 19104-6046, USA.
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Moreno-Balandrn E, Garzn M, Bdalo C, Reinoso-Surez F, de Andrs I. Sleep-wakefulness effects after microinjections of hypocretin 1 (orexin A) in cholinoceptive areas of the cat oral pontine tegmentum. Eur J Neurosci 2008; 28:331-41. [DOI: 10.1111/j.1460-9568.2008.06334.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Garcia-Rill E, Charlesworth A, Heister D, Ye M, Hayar A. The developmental decrease in REM sleep: the role of transmitters and electrical coupling. Sleep 2008; 31:673-90. [PMID: 18517037 PMCID: PMC2398758 DOI: 10.1093/sleep/31.5.673] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
STUDY OBJECTIVES This mini-review considers certain factors related to the developmental decrease in rapid eye movement (REM) sleep, which occurs in favor of additional waking time, and its relationship to developmental factors that may influence its potential role in brain development. DESIGN Specifically, we discuss some of the theories proposed for the occurrence of REM sleep and agree with the classic notion that REM sleep is, at the least, a mechanism that may play a role in the maturation of thalamocortical pathways. The developmental decrease in REM sleep occurs gradually from birth until close to puberty in the human, and in other mammals it is brief and coincides with eye and ear opening and the beginning of massive exogenous activation. Therefore, the purported role for REM sleep may change to involve a number of other functions with age. MEASUREMENTS AND RESULTS We describe recent findings showing that morphologic and physiologic properties as well as cholinergic, gamma amino-butyric acid, kainic acid, n-methyl-d-aspartic acid, noradrenergic, and serotonergic synaptic inputs to mesopontine cholinergic neurons, as well as the degree of electrical coupling between mostly noncholinergic mesopontine neurons and levels of the neuronal gap-junction protein connexin 36, change dramatically during this critical period in development. A novel mechanism for sleep-wake control based on well-known transmitter interactions, as well as electrical coupling, is described. CONCLUSION We hypothesize that a dysregulation of this process could result in life-long disturbances in arousal and REM sleep drive, leading to hypervigilance or hypovigilance such as that observed in a number of disorders that have a mostly postpubertal age of onset.
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Affiliation(s)
- Edgar Garcia-Rill
- Center for Translational Neuroscience, Department of Neurobiology & Developmental Science, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.
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Yokogawa T, Marin W, Faraco J, Pézeron G, Appelbaum L, Zhang J, Rosa F, Mourrain P, Mignot E. Characterization of sleep in zebrafish and insomnia in hypocretin receptor mutants. PLoS Biol 2008; 5:e277. [PMID: 17941721 PMCID: PMC2020497 DOI: 10.1371/journal.pbio.0050277] [Citation(s) in RCA: 248] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2007] [Accepted: 08/24/2007] [Indexed: 11/30/2022] Open
Abstract
Sleep is a fundamental biological process conserved across the animal kingdom. The study of how sleep regulatory networks are conserved is needed to better understand sleep across evolution. We present a detailed description of a sleep state in adult zebrafish characterized by reversible periods of immobility, increased arousal threshold, and place preference. Rest deprivation using gentle electrical stimulation is followed by a sleep rebound, indicating homeostatic regulation. In contrast to mammals and similarly to birds, light suppresses sleep in zebrafish, with no evidence for a sleep rebound. We also identify a null mutation in the sole receptor for the wake-promoting neuropeptide hypocretin (orexin) in zebrafish. Fish lacking this receptor demonstrate short and fragmented sleep in the dark, in striking contrast to the excessive sleepiness and cataplexy of narcolepsy in mammals. Consistent with this observation, we find that the hypocretin receptor does not colocalize with known major wake-promoting monoaminergic and cholinergic cell groups in the zebrafish. Instead, it colocalizes with large populations of GABAergic neurons, including a subpopulation of Adra2a-positive GABAergic cells in the anterior hypothalamic area, neurons that could assume a sleep modulatory role. Our study validates the use of zebrafish for the study of sleep and indicates molecular diversity in sleep regulatory networks across vertebrates. Sleep disorders are common and poorly understood. Further, how and why the brain generates sleep is the object of intense speculations. In this study, we demonstrate that a bony fish used for genetic studies sleeps and that a molecule, hypocretin, involved in causing narcolepsy, is conserved. In humans, narcolepsy is a sleep disorder associated with sleepiness, abnormal dreaming, and paralysis and insomnia. We generated a mutant fish in which the hypocretin system was disrupted. Intriguingly, this fish sleep mutant does not display sleepiness or paralysis but has a 30% reduction of its sleep time at night and a 60% decrease in sleep bout length compared with non-mutant fish. We also studied the relationships between the hypocretin system and other sleep regulatory brain systems in zebrafish and found differences in expression patterns in the brain that may explain the differences in behavior. Our study illustrates how a sleep regulatory system may have evolved across vertebrate phylogeny. Zebrafish, a powerful genetic model that has the advantage of transparency to study neuronal networks in vivo, can be used to study sleep. Zebrafish sleep, and have the receptor for the wake-inducing molecule hypocretin. While mutation in this receptor causes narcolepsy in mammals, in fish, sleep is fragmented, demonstrating differences in sleep control in vertebrates.
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Affiliation(s)
- Tohei Yokogawa
- Howard Hughes Medical Institute, Stanford University, Palo Alto, California, United States of America
| | - Wilfredo Marin
- Howard Hughes Medical Institute, Stanford University, Palo Alto, California, United States of America
| | - Juliette Faraco
- Stanford Center for Narcolepsy, Stanford University, Palo Alto, California, United States of America
| | - Guillaume Pézeron
- Ecole Normale Supérieure, Paris, France
- INSERM Unité 784, Paris, France
| | - Lior Appelbaum
- Howard Hughes Medical Institute, Stanford University, Palo Alto, California, United States of America
| | - Jian Zhang
- Stanford Center for Narcolepsy, Stanford University, Palo Alto, California, United States of America
| | - Frédéric Rosa
- Ecole Normale Supérieure, Paris, France
- INSERM Unité 784, Paris, France
| | - Philippe Mourrain
- Stanford Center for Narcolepsy, Stanford University, Palo Alto, California, United States of America
| | - Emmanuel Mignot
- Howard Hughes Medical Institute, Stanford University, Palo Alto, California, United States of America
- Stanford Center for Narcolepsy, Stanford University, Palo Alto, California, United States of America
- * To whom correspondence should be addressed. E-mail:
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Brown RE, McKenna JT, Winston S, Basheer R, Yanagawa Y, Thakkar MM, McCarley RW. Characterization of GABAergic neurons in rapid-eye-movement sleep controlling regions of the brainstem reticular formation in GAD67-green fluorescent protein knock-in mice. Eur J Neurosci 2008; 27:352-63. [PMID: 18215233 DOI: 10.1111/j.1460-9568.2008.06024.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Recent experiments suggest that brainstem GABAergic neurons may control rapid-eye-movement (REM) sleep. However, understanding their pharmacology/physiology has been hindered by difficulty in identification. Here we report that mice expressing green fluorescent protein (GFP) under the control of the GAD67 promoter (GAD67-GFP knock-in mice) exhibit numerous GFP-positive neurons in the central gray and reticular formation, allowing on-line identification in vitro. Small (10-15 microm) or medium-sized (15-25 microm) GFP-positive perikarya surrounded larger serotonergic, noradrenergic, cholinergic and reticular neurons, and > 96% of neurons were double-labeled for GFP and GABA, confirming that GFP-positive neurons are GABAergic. Whole-cell recordings in brainstem regions important for promoting REM sleep [subcoeruleus (SubC) or pontine nucleus oralis (PnO) regions] revealed that GFP-positive neurons were spontaneously active at 3-12 Hz, fired tonically, and possessed a medium-sized depolarizing sag during hyperpolarizing steps. Many neurons also exhibited a small, low-threshold calcium spike. GFP-positive neurons were tested with pharmacological agents known to promote (carbachol) or inhibit (orexin A) REM sleep. SubC GFP-positive neurons were excited by the cholinergic agonist carbachol, whereas those in the PnO were either inhibited or excited. GFP-positive neurons in both areas were excited by orexins/hypocretins. These data are congruent with the hypothesis that carbachol-inhibited GABAergic PnO neurons project to, and inhibit, REM-on SubC reticular neurons during waking, whereas carbachol-excited SubC and PnO GABAergic neurons are involved in silencing locus coeruleus and dorsal raphe aminergic neurons during REM sleep. Orexinergic suppression of REM during waking is probably mediated in part via excitation of acetylcholine-inhibited GABAergic neurons.
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Affiliation(s)
- Ritchie E Brown
- In Vitro Neurophysiology Section, Laboratory of Neuroscience, Harvard Medical School and VA Boston Healthcare System, 940 Belmont Street, Research 151-C, Brockton, MA 02301, USA.
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Min MY, Wu YW, Shih PY, Lu HW, Lin CC, Wu Y, Li MJ, Yang HW. Physiological and morphological properties of, and effect of substance P on, neurons in the A7 catecholamine cell group in rats. Neuroscience 2008; 153:1020-33. [PMID: 18440151 DOI: 10.1016/j.neuroscience.2008.03.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2007] [Revised: 03/02/2008] [Accepted: 03/03/2008] [Indexed: 11/26/2022]
Abstract
The A7 catecholamine cell group consists of noradrenergic (NAergic) neurons that project to the dorsal horn of the spinal cord. Here, we characterized their morphology and physiology properties and tested the effect of substance P (Sub-P) on them, since the results of many morphological studies suggest that A7 neurons are densely innervated by Sub-P-releasing terminals from nuclei involved in the descending inhibitory system, such as the lateral hypothalamus and periaqueductal gray area. Whole cell recordings were made from neurons located approximately 200 microm rostral to the trigeminal motor nucleus (the presumed A7 area) in sagittal brainstem slices from rats aged 7-10 days. After recording, the neurons were injected with biocytin and immunostained with antibody against dopamine-beta-hydroxylase (DBH). DBH-immunoreactive (ir) cells were presumed to be NAergic neurons. They had a large somata diameter ( approximately 20 microm) and relatively simple dendritic branching patterns. They fired action potentials (AP) spontaneously with or without blockade of synaptic inputs, and had similar properties to those of NAergic neurons in other areas, including the existence of calcium channel-mediated APs and a voltage-dependent delay in initiation of the AP (an indicator of the existence of A-type potassium currents) and an ability to be hyperpolarized by norepinephrine. Furthermore, in all DBH-ir neurons tested, Sub-P caused depolarization of the membrane potential and an increase in neuronal firing rate by acting on neurokinin-1 receptors. Non-DBH-ir neurons with a smaller somata size were also found in the A7 area. These showed great diversity in firing patterns and about half were depolarized by Sub-P. Morphological examination suggested that the non-DBH-ir neurons form contacts with DBH-ir neurons. These results provide the first description of the intrinsic regulation of membrane properties of, and the excitatory effect of Sub-P on, A7 area neurons, which play an important role in pain regulation.
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Affiliation(s)
- M-Y Min
- Department of Life Science, College of Life Science, National Taiwan University, No. 1 Sec. 4 Roosevelt Road, Taipei, Taiwan
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Garcia-Rill E, Heister DS, Ye M, Charlesworth A, Hayar A. Electrical coupling: novel mechanism for sleep-wake control. Sleep 2008; 30:1405-14. [PMID: 18041475 DOI: 10.1093/sleep/30.11.1405] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
STUDY OBJECTIVES Recent evidence suggests that certain anesthetic agents decrease electrical coupling, whereas the stimulant modafinil appears to increase electrical coupling. We investigated the potential role of electrical coupling in 2 reticular activating system sites, the subcoeruleus nucleus and in the pedunculopontine nucleus, which has been implicated in the modulation of arousal via ascending cholinergic activation of intralaminar thalamus and descending activation of the subcoeruleus nucleus to generate some of the signs of rapid eye movement sleep. DESIGN We used 6- to 30-day-old rat pups to obtain brainstem slices to perform whole-cell patch-clamp recordings. MEASUREMENTS AND RESULTS Recordings from single cells revealed the presence of spikelets, manifestations of action potentials in coupled cells, and of dye coupling of neurons in the pedunculopontine nucleus. Recordings in pairs of pedunculopontine nucleus and subcoeruleus nucleus neurons revealed that some of these were electrically coupled with coupling coefficients of approximately 2%. After blockade of fast synaptic transmission, the cholinergic agonist carbachol was found to induce rhythmic activity in pedunculopontine nucleus and subcoeruleus nucleus neurons, an effect eliminated by the gap junction blockers carbenoxolone or mefloquine. The stimulant modafinil was found to decrease resistance in neurons in the pedunculopontine nucleus and subcoeruleus nucleus after fast synaptic blockade, indicating that the effect may be due to increased coupling. CONCLUSIONS The finding of electrical coupling in specific reticular activating system cell groups supports the concept that this underlying process behind specific neurotransmitter interactions modulates ensemble activity across cell populations to promote changes in sleep-wake state.
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Affiliation(s)
- Edgar Garcia-Rill
- Center for Translational Neuroscience, Department of Neurobiology & Dev. Sci., University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.
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Abstract
This paper presents an overview of the current knowledge of the neurophysiology and cellular pharmacology of sleep mechanisms. It is written from the perspective that recent years have seen a remarkable development of knowledge about sleep mechanisms, due to the capability of current cellular neurophysiological, pharmacological and molecular techniques to provide focused, detailed, and replicable studies that have enriched and informed the knowledge of sleep phenomenology and pathology derived from electroencephalographic (EEG) analysis. This chapter has a cellular and neurophysiological/neuropharmacological focus, with an emphasis on rapid eye movement (REM) sleep mechanisms and non-REM (NREM) sleep phenomena attributable to adenosine. The survey of neuronal and neurotransmitter-related brainstem mechanisms of REM includes monoamines, acetylcholine, the reticular formation, a new emphasis on GABAergic mechanisms and a discussion of the role of orexin/hypcretin in diurnal consolidation of REM sleep. The focus of the NREM sleep discussion is on the basal forebrain and adenosine as a mediator of homeostatic control. Control is through basal forebrain extracellular adenosine accumulation during wakefulness and inhibition of wakefulness-active neurons. Over longer periods of sleep loss, there is a second mechanism of homeostatic control through transcriptional modification. Adenosine acting at the A1 receptor produces an up-regulation of A1 receptors, which increases inhibition for a given level of adenosine, effectively increasing the gain of the sleep homeostat. This second mechanism likely occurs in widespread cortical areas as well as in the basal forebrain. Finally, the results of a new series of experimental paradigms in rodents to measure the neurocognitive effects of sleep loss and sleep interruption (modeling sleep apnea) provide animal model data congruent with those in humans.
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Affiliation(s)
- Robert W McCarley
- Neuroscience Laboratory, VA Boston Healthcare System, 940 Belmont St., Brockton, MA 02301, USA.
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Heister DS, Hayar A, Charlesworth A, Yates C, Zhou YH, Garcia-Rill E. Evidence for Electrical Coupling in the SubCoeruleus (SubC) Nucleus. J Neurophysiol 2007; 97:3142-7. [PMID: 17215497 PMCID: PMC2366042 DOI: 10.1152/jn.01316.2006] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
SubCoeruleus (SubC) neurons, which are thought to modulate rapid-eye-movement (REM) sleep, were recorded in brain stem slices from 7- to 20-day rats and found to manifest spikelets, indicative of electrical coupling. Spikelets occurred spontaneously or could be induced by superfusion of the cholinergic agonist carbachol. Whole cell recordings revealed that carbachol induced membrane oscillations and spikelets in the theta frequency range in SubC neurons in the presence of fast synaptic blockers. Electrical coupling in neurons is mediated by the gap junction protein connexin 36 (Cx 36). We found that Cx 36 gene expression and protein in the mesopontine tegmentum decreased during development. Cx 36 protein levels specifically in the SubC decreased in concert with the developmental decrease in REM sleep. The presence of electrical coupling in the SubC introduces a novel potential mechanism of action for the regulation of sleep-wake states.
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Affiliation(s)
- David S Heister
- Center for Translational Neuroscience, Dept. of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, 4301 W. Markham St., Slot 847, Little Rock, AR 72205, USA
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