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Rivlin M, Navon G. Effect of reducing isoflurane level on glucosamine uptake in the mouse brain during magnetic resonance imaging studies. Neuroimage 2024; 297:120691. [PMID: 38901773 DOI: 10.1016/j.neuroimage.2024.120691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 06/11/2024] [Accepted: 06/14/2024] [Indexed: 06/22/2024] Open
Abstract
Anesthesia is often required during magnetic resonance imaging (MRI) examinations in animal studies. Anesthetic drugs differ in their capacity to interfere with homeostatic mechanisms responsible for glucose metabolism in the brain, which may create a constraint in the study design. Recent studies suggest that the chemical exchange saturation transfer (CEST) MRI scanning technique can detect localized metabolic changes in rodent brains induced by the uptake of glucose or its analogs; however, most of these studies do not account for the impact of anesthesia type on the brain metabolism. Herein, we aimed to evaluate the effect of reduced isoflurane levels on the preclinical imaging of glucosamine (GlcN) uptake in healthy mouse brains to establish optimal conditions for future brain imaging studies using the CEST MRI technique. The commonly used anesthesia protocol for longitudinal MRI examinations using 1.5% isoflurane level was compared to that using a mixture of low isoflurane (0.8%) level combined with midazolam (2 mg/kg, SC). Magnetization transfer ratio asymmetry (MTRasym) and area under the curve (AUC) analyses were used to characterize GlcN signals in the brain. The results indicated that mice injected with GlcN and anesthetized with 1.5% isoflurane exhibited low and insignificant changes in the MTRasym and AUC signals in the frontal cortex, whereas mice administered with 0.8% isoflurane combined with midazolam demonstrated a significant increase in these signals in the frontal cortex. This study highlights the diverse GlcN metabolic changes observed in mouse brains under variable levels of isoflurane anesthesia using the CEST MRI method. The results suggest that it is feasible to maintain anesthesia with low-dose isoflurane by integrating midazolam, which may enable the investigation of GlcN uptake in the brain. Thus, reducing isoflurane levels may support studies into mouse brain metabolism using the CEST MRI method and should be considered in future studies.
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Affiliation(s)
- Michal Rivlin
- School of Chemistry, Faculty of Exact Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Gil Navon
- School of Chemistry, Faculty of Exact Sciences, Tel Aviv University, Tel Aviv, Israel.
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2
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Logashkin A, Silaeva V, Mamleev A, Shumkova V, Sitdikova V, Popova Y, Suchkov D, Minlebaev M. Dexmedetomidine as a Short-Use Analgesia for the Immature Nervous System. Int J Mol Sci 2024; 25:6385. [PMID: 38928091 PMCID: PMC11204225 DOI: 10.3390/ijms25126385] [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: 04/10/2024] [Revised: 06/02/2024] [Accepted: 06/05/2024] [Indexed: 06/28/2024] Open
Abstract
Pain management in neonates continues to be a challenge. Diverse therapies are available that cause loss of pain sensitivity. However, because of side effects, the search for better options remains open. Dexmedetomidine is a promising drug; it has shown high efficacy with a good safety profile in sedation and analgesia in the immature nervous system. Though dexmedetomidine is already in use for pain control in neonates (including premature neonates) and infants as an adjunct to other anesthetics, the question remains whether it affects the neuronal activity patterning that is critical for development of the immature nervous system. In this study, using the neonatal rat as a model, the pharmacodynamic effects of dexmedetomidine on the nervous and cardiorespiratory systems were studied. Our results showed that dexmedetomidine has pronounced analgesic effects in the neonatal rat pups, and also weakly modified both the immature network patterns of cortical and hippocampal activity and the physiology of sleep cycles. Though the respiration and heart rates were slightly reduced after dexmedetomidine administration, it might be considered as the preferential independent short-term therapy for pain management in the immature and developing brain.
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Affiliation(s)
- Anatoliy Logashkin
- Laboratory of New Engineering Solutions for Modern Laboratory Research, Kazan Federal University, Kazan 420008, Russia; (A.L.)
| | - Valentina Silaeva
- Laboratory of New Engineering Solutions for Modern Laboratory Research, Kazan Federal University, Kazan 420008, Russia; (A.L.)
| | - Arsen Mamleev
- Laboratory of New Engineering Solutions for Modern Laboratory Research, Kazan Federal University, Kazan 420008, Russia; (A.L.)
| | - Viktoria Shumkova
- Laboratory of New Engineering Solutions for Modern Laboratory Research, Kazan Federal University, Kazan 420008, Russia; (A.L.)
| | - Violetta Sitdikova
- Laboratory of New Engineering Solutions for Modern Laboratory Research, Kazan Federal University, Kazan 420008, Russia; (A.L.)
| | - Yaroslavna Popova
- Laboratory of New Engineering Solutions for Modern Laboratory Research, Kazan Federal University, Kazan 420008, Russia; (A.L.)
| | - Dmitrii Suchkov
- Institut de Neurobiologie de la Méditerranée (INMED U1249), Aix-Marseille University, 13273 Marseille, France
| | - Marat Minlebaev
- Laboratory of New Engineering Solutions for Modern Laboratory Research, Kazan Federal University, Kazan 420008, Russia; (A.L.)
- Institut de Neurobiologie de la Méditerranée (INMED U1249), Aix-Marseille University, 13273 Marseille, France
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3
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Ratsifandrihamanana MR, Dard RF, Denis J, Cossart R, Picardo MA. Protocol to image and analyze hippocampal network dynamics in non-anesthetized mouse pups. STAR Protoc 2023; 4:102760. [PMID: 38041819 PMCID: PMC10701450 DOI: 10.1016/j.xpro.2023.102760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 10/03/2023] [Accepted: 11/17/2023] [Indexed: 12/04/2023] Open
Abstract
Two-photon calcium imaging is a powerful technique that has revolutionized our understanding of how neural circuit dynamics supports different behaviors and cognitive processes. However, performing imaging during development remains challenging. Here, we provide a protocol to image CA1 neurons in mouse pups as well as a pipeline of analysis to analyze and share the data. We describe steps for intracerebroventricular injection, cranial window surgery, two-photon calcium imaging, and analysis of imaging data. For complete details on the use and execution of this protocol, please refer to Dard et al.1 and Denis et al.2.
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Affiliation(s)
| | - Robin F Dard
- Turing Centre for Living Systems, Aix-Marseille University, INSERM, INMED U1249, France
| | - Julien Denis
- Turing Centre for Living Systems, Aix-Marseille University, INSERM, INMED U1249, France
| | - Rosa Cossart
- Turing Centre for Living Systems, Aix-Marseille University, INSERM, INMED U1249, France.
| | - Michel A Picardo
- Turing Centre for Living Systems, Aix-Marseille University, INSERM, INMED U1249, France.
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4
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Wu GK, Ardeshirpour Y, Mastracchio C, Kent J, Caiola M, Ye M. Amplitude- and frequency-dependent activation of layer II/III neurons by intracortical microstimulation. iScience 2023; 26:108140. [PMID: 37915592 PMCID: PMC10616374 DOI: 10.1016/j.isci.2023.108140] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 07/27/2023] [Accepted: 10/02/2023] [Indexed: 11/03/2023] Open
Abstract
Intracortical microstimulation (ICMS) has been used for the development of brain machine interfaces. However, further understanding about the spatiotemporal responses of neurons to different electrical stimulation parameters is necessary to inform the design of optimal therapies. In this study, we employed in vivo electrophysiological recording, two-photon calcium imaging, and electric field simulation to evaluate the acute effect of ICMS on layer II/III neurons. Our results show that stimulation frequency non-linearly modulates neuronal responses, whereas the magnitude of responses is linearly correlated to the electric field strength and stimulation amplitude before reaching a steady state. Temporal dynamics of neurons' responses depends more on stimulation frequency and their distance to the stimulation electrode. In addition, amplitude-dependent post-stimulation suppression was observed within ∼500 μm of the stimulation electrode, as evidenced by both calcium imaging and local field potentials. These findings provide insights for selecting stimulation parameters to achieve desirable spatiotemporal specificity of ICMS.
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Affiliation(s)
- Guangying K. Wu
- Division of Biomedical Physics, Office of Science and Engineering Laboratories, Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, MD 20993, USA
| | - Yasaman Ardeshirpour
- Division of Biomedical Physics, Office of Science and Engineering Laboratories, Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, MD 20993, USA
| | - Christina Mastracchio
- Division of Biomedical Physics, Office of Science and Engineering Laboratories, Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, MD 20993, USA
| | - Jordan Kent
- Division of Biomedical Physics, Office of Science and Engineering Laboratories, Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, MD 20993, USA
- Scientific Publications Department, Society for Neuroscience, Washington DC, USA
| | - Michael Caiola
- Division of Biomedical Physics, Office of Science and Engineering Laboratories, Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, MD 20993, USA
| | - Meijun Ye
- Division of Biomedical Physics, Office of Science and Engineering Laboratories, Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, MD 20993, USA
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5
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Klavinskis-Whiting S, Bitzenhofer S, Hanganu-Opatz I, Ellender T. Generation and propagation of bursts of activity in the developing basal ganglia. Cereb Cortex 2023; 33:10595-10613. [PMID: 37615347 PMCID: PMC10560579 DOI: 10.1093/cercor/bhad307] [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: 11/02/2022] [Revised: 08/02/2023] [Accepted: 08/03/2023] [Indexed: 08/25/2023] Open
Abstract
The neonatal brain is characterized by intermittent bursts of oscillatory activity interspersed by relative silence. Although well-characterized for many cortical areas, to what extent these propagate and interact with subcortical brain areas is largely unknown. Here, early network activity was recorded from the developing basal ganglia, including motor/somatosensory cortex, dorsal striatum, and intralaminar thalamus, during the first postnatal weeks in mice. An unsupervised detection and classification method revealed two main classes of bursting activity, namely spindle bursts and nested gamma spindle bursts, characterized by oscillatory activity at ~ 10 and ~ 30 Hz frequencies, respectively. These were reliably identified across all three brain regions and exhibited region-specific differences in their structural, spectral, and developmental characteristics. Bursts of the same type often co-occurred in different brain regions and coherence and cross-correlation analyses reveal dynamic developmental changes in their interactions. The strongest interactions were seen for cortex and striatum, from the first postnatal week onwards, and cortex appeared to drive burst events in subcortical regions. Together, these results provide the first detailed description of early network activity within the developing basal ganglia and suggest that cortex is one of the main drivers of activity in downstream nuclei during this postnatal period.
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Affiliation(s)
| | - Sebastian Bitzenhofer
- Department of Biomedical Sciences, Institute of Developmental Neurophysiology, Center for Molecular Neurobiology Hamburg (ZMNH), University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Ileana Hanganu-Opatz
- Department of Biomedical Sciences, Institute of Developmental Neurophysiology, Center for Molecular Neurobiology Hamburg (ZMNH), University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Tommas Ellender
- Department of Pharmacology, University of Oxford, Mansfield Rd, Oxford, OX13QT, United Kingdom
- Department of Biomedical Sciences, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
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6
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Yakovlev AV, Kurmashova E, Gataulina E, Gerasimova E, Khalilov I, Sitdikova GF. Maternal hyperhomocysteinemia increases seizures susceptibility of neonatal rats. Life Sci 2023; 329:121953. [PMID: 37467884 DOI: 10.1016/j.lfs.2023.121953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 07/13/2023] [Accepted: 07/14/2023] [Indexed: 07/21/2023]
Abstract
AIMS Neonatal seizures are severe pathologies which may result in long-term neurological consequences. High plasma concentrations of homocysteine - hyperhomocysteinemia (hHCy) - are associated with epilepsy. In the present study, we evaluated susceptibility to seizure of neonatal rats with prenatal hHCy. MAIN METHODS Prenatal hHCy was induced by feeding females with a high-methionine diet. Experiments were performed on pups during the first three postnatal weeks. Flurothyl-induced epileptic behavior was assessed according to Racine's scale. Epileptiform activity in the hippocampus was recorded using electrophysiological methods. The balance of excitation/inhibition, functional GABAergic inhibition and GABA reversal potential in hippocampal neurons were analyzed. KEY FINDINGS Rats with hHCy developed more severe stages of behavioral patterns during flurothyl-induced epilepsy with shorter latency. Electrophysiological recordings demonstrated higher background neuronal activity in rats with hHCy. Seizure-like events triggered by flurothyl (in vivo) or 4-aminopyridine (in vitro) showed shorter latency, higher power and amplitude. An increased glutamate/GABA synaptic ratio was shown in the pyramidal neurons of rats with hHCy and more slices demonstrated excitation by isoguvacine, a selective GABA(A) receptor agonist, during the first and second postnatal weeks. The GABA driving force and the reversal potential of GABA(A) currents were more positive during the second postnatal week for hHCy rats. SIGNIFICANCE The higher susceptibility to seizures in rats with prenatal hHCy due to a shift in the balance of excitation/inhibition toward excitation may underlie the clinical evidence about the association of hHCy with an increased risk of epilepsy.
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Affiliation(s)
- A V Yakovlev
- Department of Human and Animal Physiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya str 18, Kazan 420008, Russia.
| | - E Kurmashova
- Department of Human and Animal Physiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya str 18, Kazan 420008, Russia
| | - E Gataulina
- Department of Human and Animal Physiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya str 18, Kazan 420008, Russia
| | - E Gerasimova
- Department of Human and Animal Physiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya str 18, Kazan 420008, Russia
| | - I Khalilov
- Institut de Neurobiologie de la Méditerranée, INMED UMR901 Parc scientifique de Luminy, 163 avenue de Luminy BP13 - 13273, Marseille cedex 09, France; Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya str 18, Kazan 420008, Russia
| | - G F Sitdikova
- Department of Human and Animal Physiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya str 18, Kazan 420008, Russia
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7
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Mingazov B, Vinokurova D, Zakharov A, Khazipov R. Comparative Study of Terminal Cortical Potentials Using Iridium and Ag/AgCl Electrodes. Int J Mol Sci 2023; 24:10769. [PMID: 37445945 DOI: 10.3390/ijms241310769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 06/19/2023] [Accepted: 06/26/2023] [Indexed: 07/15/2023] Open
Abstract
Brain ischemia induces slow voltage shifts in the cerebral cortex, including waves of spreading depolarization (SD) and negative ultraslow potentials (NUPs), which are considered as brain injury markers. However, different electrode materials and locations yield variable SD and NUP features. Here, we compared terminal cortical events during isoflurane or sevoflurane euthanasia using intracortical linear iridium electrode arrays and Ag/AgCl-based electrodes in the rat somatosensory cortex. Inhalation of anesthetics caused respiratory arrest, associated with hyperpolarization and followed by SD and NUP on both Ir and Ag electrodes. Ag-NUPs were bell shaped and waned within half an hour after death. Ir-NUPs were biphasic, with the early fast phase corresponding to Ag-NUP, and the late absent on Ag electrodes, phase of a progressive depolarizing voltage shift reaching -100 mV by two hours after death. In addition, late Ir-NUPs were more ample in the deep layers than at the cortical surface. Thus, intracortical Ag and Ir electrodes reliably assess early manifestations of terminal brain injury including hyperpolarization, SD and the early phase of NUP, while the late, giant amplitude phase of NUP, which is present only on Ir electrodes, is probably related to the sensitivity of Ir electrodes to a yet unidentified factor related to brain death.
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Affiliation(s)
- Bulat Mingazov
- Laboratory of Neurobiology, Kazan Federal University, Kazan 420008, Russia
| | - Daria Vinokurova
- Laboratory of Neurobiology, Kazan Federal University, Kazan 420008, Russia
| | - Andrei Zakharov
- Laboratory of Neurobiology, Kazan Federal University, Kazan 420008, Russia
- Department of Physiology, Kazan State Medical University, Kazan 420012, Russia
| | - Roustem Khazipov
- Laboratory of Neurobiology, Kazan Federal University, Kazan 420008, Russia
- Institut de Neurobiologie de la Méditerranée (Inserm U1249), Aix-Marseille Université, 13273 Marseille, France
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8
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Egashira T, Nakagawa-Tamagawa N, Abzhanova E, Kawae Y, Kohara A, Koitabashi R, Mizuno H, Mizuno H. In vivo two-photon calcium imaging of cortical neurons in neonatal mice. STAR Protoc 2023; 4:102245. [PMID: 37119143 PMCID: PMC10173855 DOI: 10.1016/j.xpro.2023.102245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 01/20/2023] [Accepted: 03/24/2023] [Indexed: 04/30/2023] Open
Abstract
In vivo calcium imaging is essential to elucidate unique synchronous activities observed in the developing brain. Here, we present a protocol to image and analyze activity patterns in neonatal mouse neocortex in a single-cell level. We describe steps for in utero electroporation, cranial window surgery, two-photon imaging, and activity correlation analysis. This protocol facilitates the understanding of neuronal activities and activity-dependent circuit formation during development. For complete details on the use and execution of this protocol, please refer to Mizuno et al. (2014),1 Mizuno et al. (2018a),2 and Mizuno et al. (2018b).3.
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Affiliation(s)
- Takamitsu Egashira
- Laboratory of Multi-Dimensional Imaging, International Research Center for Medical Sciences (IRCMS), Kumamoto University, Kumamoto 860-0811, Japan; Graduate School of Medical Sciences, Kumamoto University, Kumamoto 860-0811, Japan
| | - Nao Nakagawa-Tamagawa
- Department of Physiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544, Japan.
| | - Elvira Abzhanova
- Laboratory of Multi-Dimensional Imaging, International Research Center for Medical Sciences (IRCMS), Kumamoto University, Kumamoto 860-0811, Japan; Graduate School of Medical Sciences, Kumamoto University, Kumamoto 860-0811, Japan
| | - Yuzuki Kawae
- Laboratory of Multi-Dimensional Imaging, International Research Center for Medical Sciences (IRCMS), Kumamoto University, Kumamoto 860-0811, Japan
| | - Ayami Kohara
- Laboratory of Multi-Dimensional Imaging, International Research Center for Medical Sciences (IRCMS), Kumamoto University, Kumamoto 860-0811, Japan
| | - Ryoko Koitabashi
- Laboratory of Multi-Dimensional Imaging, International Research Center for Medical Sciences (IRCMS), Kumamoto University, Kumamoto 860-0811, Japan
| | - Hiromi Mizuno
- Laboratory of Multi-Dimensional Imaging, International Research Center for Medical Sciences (IRCMS), Kumamoto University, Kumamoto 860-0811, Japan
| | - Hidenobu Mizuno
- Laboratory of Multi-Dimensional Imaging, International Research Center for Medical Sciences (IRCMS), Kumamoto University, Kumamoto 860-0811, Japan; Graduate School of Medical Sciences, Kumamoto University, Kumamoto 860-0811, Japan.
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9
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Luhmann HJ. Malformations-related neocortical circuits in focal seizures. Neurobiol Dis 2023; 178:106018. [PMID: 36706927 DOI: 10.1016/j.nbd.2023.106018] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 01/18/2023] [Accepted: 01/23/2023] [Indexed: 01/25/2023] Open
Abstract
This review article gives an overview on the molecular, cellular and network mechanisms underlying focal seizures in neocortical networks with developmental malformations. Neocortical malformations comprise a large variety of structural abnormalities associated with epilepsy and other neurological and psychiatric disorders. Genetic or acquired disorders of neocortical cell proliferation, neuronal migration and/or programmed cell death may cause pathologies ranging from the expression of dysmorphic neurons and heterotopic cell clusters to abnormal layering and cortical misfolding. After providing a brief overview on the pathogenesis and structure of neocortical malformations in humans, animal models are discussed and how they contributed to our understanding on the mechanisms of neocortical hyperexcitability associated with developmental disorders. State-of-the-art molecular biological and electrophysiological techniques have been also used in humans and on resectioned neocortical tissue of epileptic patients and provide deep insights into the subcellular, cellular and network mechanisms contributing to focal seizures. Finally, a brief outlook is given how novel models and methods can shape translational research in the near future.
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Affiliation(s)
- Heiko J Luhmann
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, Mainz, Germany.
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10
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Caravaca-Rodriguez D, Suaning GJ, Barriga-Rivera A. Cross-modal activation of the primary visual cortex by auditory stimulation in RCS rats: considerations in visual prosthesis. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2022; 2022:1711-1714. [PMID: 36086188 DOI: 10.1109/embc48229.2022.9871504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
An important brain re-wiring, the so-called cross-modal plasticity, occurs during progression of retinal degenerative diseases to compensate for lack of visual input. The visual cortex does not go 'unused', instead it is devoted to processing other sensory modalities. In this study we recorded, in the visual cortex, visual- and auditory-evoked potentials in an anesthetized murine model of retinal degeneration. The latency to the first peak of the recorded local field potentials was used to assess the speed of the response. Visual responses occurred significantly faster in the control group. Conversely, auditory responses appeared significantly faster in animals with retinal degeneration. This suggests the compensatory neural rewiring is optimizing the performance of other sensory modalities, hearing in this case. This phenomenon may play an important role in visual neuro-rehabilitation. Whether or not it can promote or deter the interpretation of artificially encoded neural signals from a visual prosthesis remains to be studied.
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Sturgill B, Radhakrishna R, Thai TTD, Patnaik SS, Capadona JR, Pancrazio JJ. Characterization of Active Electrode Yield for Intracortical Arrays: Awake versus Anesthesia. MICROMACHINES 2022; 13:mi13030480. [PMID: 35334770 PMCID: PMC8955818 DOI: 10.3390/mi13030480] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 03/17/2022] [Accepted: 03/18/2022] [Indexed: 12/04/2022]
Abstract
Intracortical microelectrode arrays are used for recording neural signals at single-unit resolution and are promising tools for studying brain function and developing neuroprosthetics. Research is being done to increase the chronic performance and reliability of these probes, which tend to decrease or fail within several months of implantation. Although recording paradigms vary, studies focused on assessing the reliability and performance of these devices often perform recordings under anesthesia. However, anesthetics—such as isoflurane—are known to alter neural activity and electrophysiologic function. Therefore, we compared the neural recording performance under anesthesia (2% isoflurane) followed by awake conditions for probes implanted in the motor cortex of both male and female Sprague-Dawley rats. While the single-unit spike rate was significantly higher by almost 600% under awake compared to anesthetized conditions, we found no difference in the active electrode yield between the two conditions two weeks after surgery. Additionally, the signal-to-noise ratio was greater under anesthesia due to the noise levels being nearly 50% greater in awake recordings, even though there was a 14% increase in the peak-to-peak voltage of distinguished single units when awake. We observe that these findings are similar for chronic time points as well. Our observations indicate that either anesthetized or awake recordings are acceptable for studies assessing the chronic reliability and performance of intracortical microelectrode arrays.
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Affiliation(s)
- Brandon Sturgill
- Department of Bioengineering, The University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX 75080, USA; (B.S.); (R.R.); (T.T.D.T.); (S.S.P.)
| | - Rahul Radhakrishna
- Department of Bioengineering, The University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX 75080, USA; (B.S.); (R.R.); (T.T.D.T.); (S.S.P.)
| | - Teresa Thuc Doan Thai
- Department of Bioengineering, The University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX 75080, USA; (B.S.); (R.R.); (T.T.D.T.); (S.S.P.)
| | - Sourav S. Patnaik
- Department of Bioengineering, The University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX 75080, USA; (B.S.); (R.R.); (T.T.D.T.); (S.S.P.)
| | - Jeffrey R. Capadona
- Department of Biomedical Engineering, Case Western Reserve University, Advanced Platform Technology Center, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH 44106, USA;
| | - Joseph J. Pancrazio
- Department of Bioengineering, The University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX 75080, USA; (B.S.); (R.R.); (T.T.D.T.); (S.S.P.)
- Correspondence:
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12
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Sun Q, Hu Y, Deng S, Xiong Y, Huang Z. A visualization pipeline for <i>in vivo</i> two-photon volumetric astrocytic calcium imaging. J Biomed Res 2022; 36:358-367. [PMID: 36130733 PMCID: PMC9548438 DOI: 10.7555/jbr.36.20220099] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Astrocytes, the multi-functional glial cells with the most abundant population in the brain, integrate information across their territories to regulate neuronal synaptic and cerebrovascular activities. Astrocytic calcium (Ca2+) signaling is the major readout of cellular functional state of astrocytes. The conventional two-photon in vivo imaging usually focuses on a single horizontal focal plane to capture the astrocytic Ca2+ signals, which leaves >80% spatial information undetected. To fully probe the Ca2+ activity across the whole astrocytic territory, we developed a pipeline for imaging and visualizing volumetric astrocytic Ca2+ time-lapse images. With the pipeline, we discovered a new signal distribution pattern from three-dimensional (3D) astrocytic Ca2+ imaging data of mice under isoflurane anesthetic states. The tools developed in this study enable a better understanding of the spatiotemporal patterns of astrocytic activity in 3D space.
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Affiliation(s)
- Qian Sun
- Department of Pharmacology, School of Basic Medical Science, Fudan University, Shanghai 200032, China
| | - Yusi Hu
- Department of Pharmacology, School of Basic Medical Science, Fudan University, Shanghai 200032, China
- State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China
| | - Saiyue Deng
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Yanyu Xiong
- Department of Pharmacology, School of Basic Medical Science, Fudan University, Shanghai 200032, China
- State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China
| | - Zhili Huang
- Department of Pharmacology, School of Basic Medical Science, Fudan University, Shanghai 200032, China
- State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China
- Zhili Huang, Department of Pharmacology, School of Basic Medical Science, Fudan University, 130 Dong'an Road, Shanghai 200032, China. Tel/Fax: +86-21-54237043/+86-21-54237103, E-mail:
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Effects of urethane and isoflurane on the sensory evoked response and local blood flow in the early postnatal rat somatosensory cortex. Sci Rep 2021; 11:9567. [PMID: 33953244 PMCID: PMC8099888 DOI: 10.1038/s41598-021-88461-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 03/31/2021] [Indexed: 01/01/2023] Open
Abstract
Functional studies in the central nervous system are often conducted using anesthesia. While the dose-dependent effects of anesthesia on neuronal activity have been extensively characterized in adults, little is known about the effects of anesthesia on cortical activity and cerebral blood flow in the immature central nervous system. Substitution of electrophysiological recordings with the less-invasive technique of optical intrinsic signal imaging (OIS) in vivo allowed simultaneous recordings of sensory-evoked functional response and local blood flow changes in the neonatal rat barrel cortex. Using OIS we characterize the effects of two widely used anesthetics—urethane and isoflurane. We found that both anesthetics suppressed the sensory-evoked optical intrinsic signal in a dose-dependent manner. Dependence of the cortical response suppression matched the exponential decay model. At experimental levels of anesthesia, urethane affected the evoked cortical response less than isoflurane, which is in agreement with the results of electrophysiological recordings demonstrated by other authors. Changes in oxygenation and local blood flow also showed negative correlation with both anesthetics. The high similarity in immature patterns of activity recorded in different regions of the developing cortex suggested similar principles of development regardless of the cortical region. Therefore the indicated results should be taken into account during functional explorations in the entire developing cortex. Our results also point to urethane as the anesthetic of choice in non-survival experimental recordings in the developing brain as it produces less prominent impairment of cortical neuronal activity in neonatal animals.
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Hyperhomocysteinemia increases susceptibility to cortical spreading depression associated with photophobia, mechanical allodynia, and anxiety in rats. Behav Brain Res 2021; 409:113324. [PMID: 33915239 DOI: 10.1016/j.bbr.2021.113324] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 04/23/2021] [Accepted: 04/23/2021] [Indexed: 11/23/2022]
Abstract
Epidemiological data suggest that elevated homocysteine is associated with migraine with aura. However, how homocysteine contributes to migraine is still unclear. Here, we tested whether hyperhomocysteinemia (hHCY) promotes cortical spreading depression (CSD), a phenomenon underlying migraine with aura, and whether hHCY contributes to pain behavior. hHCY was induced by dietary methionine in female rats while the testing was performed on their 6-8week-old offspring. CSD and multiple unit activity (MUA) induced by KCl were recorded from the primary somatosensory cortex, S1, using multichannel electrodes. In hHCY rats, compared to control, we found: i) higher probability of CSD occurrence; ii) induction of CSD by lower concentrations of KCl; iii) faster horizontal propagation of CSD; iv) smaller CSD with longer duration; v) higher frequency of MUA at CSD onset along with slower reappearance. Rats with hHCY demonstrated high level of locomotor activity and grooming while spent less time in the central area of the open field, indicating anxiety. These animals showed light sensitivity and facial mechanical allodinia. Thus, hHCY acquired at birth promotes multiple features of migraine such as higher cortical excitability, mechanical allodynia, photophobia, and anxiety. Our results provide the first experimental explanation for the higher occurrence of migraine with aura in patients with hHCY.
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Ben-Ari Y, Delpire E. Phenobarbital, midazolam, bumetanide, and neonatal seizures: The devil is in the details. Epilepsia 2021; 62:935-940. [PMID: 33534145 PMCID: PMC8035263 DOI: 10.1111/epi.16830] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 01/11/2021] [Indexed: 12/21/2022]
Abstract
Kaila, Löscher, and colleagues report that phenobarbital (PHB) and midazolam (MDZ) attenuate neonatal seizures following birth asphyxia, but the former only when applied before asphyxia and the latter before or after the triggering insult. In contrast, the NKCC1 chloride importer antagonist bumetanide (BUM) had no effect whether applied alone or with PHB. The observations are compelling and in accord with earlier studies. However, there are several general issues that deserve discussion. What is the clinical relevance of these data and the validity of animal models of encephalopathic seizures? Why is it that although they act on similar targets, these agents have different efficacy? Are both PHB and MDZ actions restricted to γ-aminobutyric acidergic (GABAergic) mechanisms? Why is BUM inefficient in attenuating seizures but capable of reducing the severity of other brain disorders? We suggest that the relative failure of antiepileptic drugs (AEDs) to treat this severe life-threatening condition is in part explicable by the recurrent seizures that shift the polarity of GABA, thereby counteracting their effects on their target. AEDs might be efficient after a few seizures but not recurrent ones. In addition, PHB and MDZ actions are not limited to GABA signals. BUM efficiently attenuates autism symptomatology notably in patients with tuberous sclerosis but does not reduce the recurrent seizures, illustrating the uniqueness of epilepsies. Therefore, the efficacy of AEDs to treat babies with encephalopathic seizures will depend on the history and severity of the seizures prior to their administration, challenging a universal common underlying mechanism.
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Affiliation(s)
- Yehezkel Ben-Ari
- Neurochlore, Fundamental Research Department, Ben-Ari Institute of Neuroarcheology (IBEN), Marseille, France.,Correspondence should be addressed to Dr. Yehezkel Ben-Ari, , Address: Neurochlore, Parc Scientifique et Technologique de Luminy, Bâtiment Beret-Delaage, Zone Luminy Biotech Entreprises, Case 922, 163 avenue de Luminy, 13288 Marseille Cedex 9. Phone number: +33 (0)4 86 94 85 02
| | - Eric Delpire
- Department of Anesthesiology, Vanderbilt University Medical School, Nashville, TN 37232, USA
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Li L, Lu S, Fan X. Silencing of miR-302b-3p alleviates isoflurane-induced neuronal injury by regulating PTEN expression and AKT pathway. Brain Res Bull 2020; 168:89-99. [PMID: 33370590 DOI: 10.1016/j.brainresbull.2020.12.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 12/21/2020] [Accepted: 12/22/2020] [Indexed: 12/17/2022]
Abstract
Isoflurane (ISO) is an anesthesia and can result in neuron injury. A previous study has indicated that microRNA-302b-3p (miR-302b-3p) exerts a crucial function in modulating cerebral ischemia/reperfusion damage-induced neuronal injury. We sought to examine the role of miR-302b-3p in ISO-induced neuronal injury. In the present study, the effects of miR-302b-3p on ISO-induced neuron injury were investigated by MTT and TUNEL assays. We discovered that ISO stimulation led to miR-302b-3p upregulation and neuronal injury. MiR-302b-3p silencing exerted protective effects against ISO induced neuronal injury. In addition, phosphatase and tensin homologue deleted on chromosome 10 (PTEN) was a direct downstream target gene of miR-302b-3p. MiR-302b-3p targets the 3'UTR of PTEN to inhibit its mRNA expression, and further reduces its protein expression. Silencing of PTEN partially reversed the protecting effects of silenced miR-302b-3p on ISO-induced injury of hippocampal neurons. Further, miR-302b-3p activated the AKT signaling pathway in neurons exposed to ISO by downregulation of PTEN. Finally, in vivo studies revealed that silencing of miR-302b-3p alleviates ISO-induced injury and spatial memory impairment of rats partly by upregulation of PTEN. Overall, our findings indicated that miR-302b-3p targets PTEN to activate the AKT pathway, and silencing of miR-302b-3p plays a neuroprotective role in ISO-induced neuronal injury by the PTEN/AKT pathway, suggesting miR-302b-3p as a crucial target for ISO-induced neuronal injury.
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Affiliation(s)
- Linlin Li
- Department of Anesthesiology, China-Japan Union Hospital of Jilin University, No.126 Xiantai Street, Changchun, 130033, Jilin, China
| | - Shan Lu
- Department of Anesthesiology, China-Japan Union Hospital of Jilin University, No.126 Xiantai Street, Changchun, 130033, Jilin, China
| | - Xiaodi Fan
- Department of Anesthesiology, China-Japan Union Hospital of Jilin University, No.126 Xiantai Street, Changchun, 130033, Jilin, China.
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Saito A, Wada K, Suzuki Y, Nakasono S. The response of the neuronal activity in the somatosensory cortex after high-intensity intermediate-frequency magnetic field exposure to the spinal cord in rats under anesthesia and waking states. Brain Res 2020; 1747:147063. [PMID: 32818531 DOI: 10.1016/j.brainres.2020.147063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 08/08/2020] [Accepted: 08/14/2020] [Indexed: 12/01/2022]
Abstract
Novel technologies using the intermediate-frequency magnetic field (IF-MF) in living environments are becoming popular with the advance in electricity utilization. However, the biological effects induced by the high-intensity and burst-type IF-MF exposure used in the wireless power transfer technologies for electric vehicles or medical devices, such as the magnetic stimulation techniques, are not well understood. Here, we developed an experimental platform using rats, that combined an 18 kHz, high-intensity (Max. 88 mT), Gaussian-shaped burst IF-MF exposure system with an in vivo extracellular recording system. In this paper, we aimed to report the qualitative differences in stimulus responses in the regions of the somatosensory cortex and peripheral nerve fibers that were induced by the IF-MF exposure to the rat spinal cord. We also report the modulation of the stimulus responses in the somatosensory cortex under anesthesia or waking states. Using this experimental platform, we succeeded in the detection of the motor evoked potentials or the neuronal activity in the somatosensory cortex that was induced by the IF-MF exposure to the spinal cord in rats. Compared to the state of anesthesia, the neuronal activities in the somatosensory cortex was enhanced during the waking state. On the other hand, these neuronal responses could not be confirmed by the IF-MF exposure-related coil sound only. Our experimental results indicated the basic knowledge of the biological responses and excitation mechanisms of the spinal cord stimulation by the IF-MF exposure.
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Affiliation(s)
- Atsushi Saito
- Biological Environment Sector, Environmental Science Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), 1646 Abiko, Abiko-shi, Chiba, Japan.
| | - Keiji Wada
- Department of Electrical Engineering and Computer Science, Graduate School of Systems Design, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachioji-shi, Tokyo, Japan.
| | - Yukihisa Suzuki
- Department of Electrical Engineering and Computer Science, Graduate School of Systems Design, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachioji-shi, Tokyo, Japan.
| | - Satoshi Nakasono
- Biological Environment Sector, Environmental Science Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), 1646 Abiko, Abiko-shi, Chiba, Japan.
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Quantitative definition of neurobehavior, vision, hearing and brain volumes in macaques congenitally exposed to Zika virus. PLoS One 2020; 15:e0235877. [PMID: 33091010 PMCID: PMC7580995 DOI: 10.1371/journal.pone.0235877] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 10/05/2020] [Indexed: 12/14/2022] Open
Abstract
Congenital Zika virus (ZIKV) exposure results in a spectrum of disease ranging from severe birth defects to delayed onset neurodevelopmental deficits. ZIKV-related neuropathogenesis, predictors of birth defects, and neurodevelopmental deficits are not well defined in people. Here we assess the methodological and statistical feasibility of a congenital ZIKV exposure macaque model for identifying infant neurobehavior and brain abnormalities that may underlie neurodevelopmental deficits. We inoculated five pregnant macaques with ZIKV and mock-inoculated one macaque in the first trimester. Following birth, growth, ocular structure/function, brain structure, hearing, histopathology, and neurobehavior were quantitatively assessed during the first week of life. We identified the typical pregnancy outcomes of congenital ZIKV infection, with fetal demise and placental abnormalities. We estimated sample sizes needed to define differences between groups and demonstrated that future studies quantifying brain region volumes, retinal structure, hearing, and visual pathway function require a sample size of 14 animals per group (14 ZIKV, 14 control) to detect statistically significant differences in at least half of the infant exam parameters. Establishing the parameters for future studies of neurodevelopmental outcomes following congenital ZIKV exposure in macaques is essential for robust and rigorous experimental design.
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19
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Distinct Age-Dependent C Fiber-Driven Oscillatory Activity in the Rat Somatosensory Cortex. eNeuro 2020; 7:ENEURO.0036-20.2020. [PMID: 32759177 PMCID: PMC7545434 DOI: 10.1523/eneuro.0036-20.2020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 07/03/2020] [Accepted: 07/27/2020] [Indexed: 11/21/2022] Open
Abstract
When skin afferents are activated, the sensory signals are transmitted to the spinal cord and eventually reach the primary somatosensory cortex (S1), initiating the encoding of the sensory percept in the brain. While subsets of primary afferents mediate specific somatosensory information from an early age, the subcortical pathways that transmit this information undergo striking changes over the first weeks of life, reflected in the gradual emergence of specific sensory behaviors. We therefore hypothesized that this period is associated with differential changes in the encoding of incoming afferent volleys in S1. To test this, we compared S1 responses to A fiber skin afferent stimulation and A + C skin afferent fiber stimulation in lightly anaesthetized male rats at postnatal day (P)7, P14, P21, and P30. Differences in S1 activity following A and A + C fiber stimulation changed dramatically over this period. At P30, A + C fiber stimulation evoked significantly larger γ, β, and α energy increases compared with A fiber stimulation alone. At younger ages, the changes in S1 oscillatory activity evoked by the two afferent volleys were not significantly different. Silencing TRPV1+ C fibers with QX-314 significantly reduced the γ and β S1 oscillatory energy increases evoked by A + C fibers, at P30 and P21, but not at younger ages. Thus, C fibers differentially modulate S1 oscillatory activity only from the third postnatal week, well after the functional maturation of the somatosensory cortex. This age-related change in afferent evoked S1 oscillatory activity may underpin the maturation of sensory discrimination in the developing brain.
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Modulation of Spontaneous and Light-Induced Activity in the Rat Dorsal Lateral Geniculate Nucleus by General Brain State Alterations under Urethane Anesthesia. Neuroscience 2019; 413:279-293. [DOI: 10.1016/j.neuroscience.2019.06.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 05/23/2019] [Accepted: 06/12/2019] [Indexed: 12/21/2022]
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21
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Salmi M, Del Gallo F, Minlebaev M, Zakharov A, Pauly V, Perron P, Pons‐Bennaceur A, Corby‐Pellegrino S, Aniksztejn L, Lenck‐Santini P, Epsztein J, Khazipov R, Burnashev N, Bertini G, Szepetowski P. Impaired vocal communication, sleep‐related discharges, and transient alteration of slow‐wave sleep in developing mice lacking the GluN2A subunit of
N
‐methyl‐
d
‐aspartate receptors. Epilepsia 2019; 60:1424-1437. [DOI: 10.1111/epi.16060] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 05/13/2019] [Accepted: 05/13/2019] [Indexed: 02/04/2023]
Affiliation(s)
- Manal Salmi
- National Institute of Health and Medical Research INSERM Joint Research Unit UMR 1249Mediterranean Institute of Neurobiology INMEDAix‐Marseille University Marseille France
| | - Federico Del Gallo
- Department of Neurosciences, Biomedicine, and Movement Sciences University of Verona Verona Italy
| | - Marat Minlebaev
- National Institute of Health and Medical Research INSERM Joint Research Unit UMR 1249Mediterranean Institute of Neurobiology INMEDAix‐Marseille University Marseille France
- Laboratory of Neurobiology Kazan Federal University Kazan Russia
| | - Andrey Zakharov
- Laboratory of Neurobiology Kazan Federal University Kazan Russia
| | - Vanessa Pauly
- Public Health Laboratory, Recognized Team (EA) 3279 Associate Center for Drug Dependency and Addictovigilance Faculty of Medicine Aix‐Marseille University Marseille France
| | - Pauline Perron
- National Institute of Health and Medical Research INSERM Joint Research Unit UMR 1249Mediterranean Institute of Neurobiology INMEDAix‐Marseille University Marseille France
| | - Alexandre Pons‐Bennaceur
- National Institute of Health and Medical Research INSERM Joint Research Unit UMR 1249Mediterranean Institute of Neurobiology INMEDAix‐Marseille University Marseille France
| | - Séverine Corby‐Pellegrino
- National Institute of Health and Medical Research INSERM Joint Research Unit UMR 1249Mediterranean Institute of Neurobiology INMEDAix‐Marseille University Marseille France
| | - Laurent Aniksztejn
- National Institute of Health and Medical Research INSERM Joint Research Unit UMR 1249Mediterranean Institute of Neurobiology INMEDAix‐Marseille University Marseille France
| | - Pierre‐Pascal Lenck‐Santini
- National Institute of Health and Medical Research INSERM Joint Research Unit UMR 1249Mediterranean Institute of Neurobiology INMEDAix‐Marseille University Marseille France
| | - Jérôme Epsztein
- National Institute of Health and Medical Research INSERM Joint Research Unit UMR 1249Mediterranean Institute of Neurobiology INMEDAix‐Marseille University Marseille France
| | - Rustem Khazipov
- National Institute of Health and Medical Research INSERM Joint Research Unit UMR 1249Mediterranean Institute of Neurobiology INMEDAix‐Marseille University Marseille France
- Laboratory of Neurobiology Kazan Federal University Kazan Russia
| | - Nail Burnashev
- National Institute of Health and Medical Research INSERM Joint Research Unit UMR 1249Mediterranean Institute of Neurobiology INMEDAix‐Marseille University Marseille France
| | - Giuseppe Bertini
- Department of Neurosciences, Biomedicine, and Movement Sciences University of Verona Verona Italy
| | - Pierre Szepetowski
- National Institute of Health and Medical Research INSERM Joint Research Unit UMR 1249Mediterranean Institute of Neurobiology INMEDAix‐Marseille University Marseille France
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22
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The effect of sevoflurane and isoflurane anesthesia on single unit and local field potentials. Exp Brain Res 2019; 237:1521-1529. [PMID: 30919011 DOI: 10.1007/s00221-019-05528-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 03/22/2019] [Indexed: 10/27/2022]
Abstract
Volatile general anesthetics are used commonly in adults and children, yet their mechanisms of action are complex and the changes in single unit firing and synaptic activity that underlie the broad decreases in neuronal activity induced by these drugs have not been well characterized. Capturing such changes throughout the anesthesia process is important for comparing the effects of different anesthetics and gaining a better understanding of their mechanisms of action and their impact on different brain regions. Using chronically implanted electrodes in the rabbit somatosensory cortex, we compared the effects of two common general anesthetics, isoflurane, and sevoflurane, on cortical neurons. Single unit activity and local field potentials (LFP) were recorded continuously before and during anesthetic delivery at 1 MAC, as well as during recovery. Our findings show that although isoflurane and sevoflurane belong to the same class of volatile general anesthetics, their effects upon cortical single units and LFP were quite different. Overall, the suppression of neuronal firing was greater and more uniform under sevoflurane. Moreover, the changes in LFP frequency bands suggest that effect of anesthesia upon beta oscillations does not necessarily depend on the level of single unit activity, but rather on the changes in GABA/glutamate neurotransmission induced by each drug.
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23
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Wang X, Shan Y, Tang Z, Gao L, Liu H. Neuroprotective effects of dexmedetomidine against isoflurane-induced neuronal injury via glutamate regulation in neonatal rats. DRUG DESIGN DEVELOPMENT AND THERAPY 2018; 13:153-160. [PMID: 30613136 PMCID: PMC6306062 DOI: 10.2147/dddt.s163197] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Background Considerable evidences support the finding that the anesthesia reagent isoflurane increases neuronal cell death in young rats. Recent studies have shown that dexmedetomidine can reduce isoflurane-induced neuronal injury, but the mechanism remains unclear. We investigated whether isoflurane cause neurotoxicity to the central nervous system by regulating the N-methyl-D-aspartate receptor (NMDAR) and excitatory amino acid transporter1 (EAAT1) in young rats. Furthermore, we examined if dexmedetomidine could decrease isoflurane-induced neurotoxicity. Methods Neonatal rats (postnatal day 7, n=144) were randomly divided into four groups of 36 animals each: control (saline injection without isoflurane); isoflurane (2% for 4 h); isoflurane + single dose of dexmedetomidine (75 µg/kg, 20 min before the start of 2% isoflurane for 4 h); and isoflurane + dual doses of dexmedetomidine (25 µg/kg, 20 min before and 2 h after start of isoflurane at 2% for 4 h). Six neonates from each group were euthanatized at 2 h, 12 h, 24 h, 3 days, 7 days and 28 days post-anesthesia. Hippocampi were collected and processed for protein extraction. Expression levels of the NMDAR subunits NR2A and NR2B, EAAT1 and caspase-3 were measured by western blot analysis. Results Protein levels of NR2A, EAAT1 and caspase-3 were significantly increased in hippocampus of the isoflurane group from 2 h to 3 days, while NR2B levels were decreased. However, the -induced increase in NR2A, EAAT1 and caspase-3 and the decrease in NR2B in isoflurane-exposed rats were ameliorated in the rats treated with single or dual doses of dexmedetomidine. Isoflurane-induced neuronal damage in neonatal rats is due in part to the increase in NR2A and EAAT1 and the decrease in NR2B in the hippocampus. Conclusion Dexmedetomidine protects the brain against the use of isoflurane through the regulation of NR2A, NR2B and EAAT1. However, using the same amount of dexmedetomidine, the trend of protection is basically the same.
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Affiliation(s)
- Xue Wang
- Department of Anesthesiology, Shengjing Hospital, China Medical University, Shenyang 110004, China, .,Department of Anesthesiology, Xiangyang Central Hospital, Affiliated Hospital of Hubei University of Arts and Sciences, Xiangyang 441000, China
| | - Yangyang Shan
- Department of Anesthesiology, Shengjing Hospital, China Medical University, Shenyang 110004, China,
| | - Zhiyin Tang
- Department of Anesthesiology, Shengjing Hospital, China Medical University, Shenyang 110004, China,
| | - Linlin Gao
- Department of Medical Research, Shengjing Hospital, China Medical University, Shenyang 110004, China
| | - Hongtao Liu
- Department of Anesthesiology, Shengjing Hospital, China Medical University, Shenyang 110004, China,
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Gardner AT, Strathman HJ, Warren DJ, Walker RM. Impedance and Noise Characterizations of Utah and Microwire Electrode Arrays. ACTA ACUST UNITED AC 2018. [DOI: 10.1109/jerm.2018.2862417] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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25
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Akman O, Raol YH, Auvin S, Cortez MA, Kubova H, de Curtis M, Ikeda A, Dudek FE, Galanopoulou AS. Methodologic recommendations and possible interpretations of video-EEG recordings in immature rodents used as experimental controls: A TASK1-WG2 report of the ILAE/AES Joint Translational Task Force. Epilepsia Open 2018; 3:437-459. [PMID: 30525114 PMCID: PMC6276777 DOI: 10.1002/epi4.12262] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/14/2018] [Indexed: 01/30/2023] Open
Abstract
The use of immature rodents to study physiologic aspects of cortical development requires high‐quality recordings electroencephalography (EEG) with simultaneous video recording (vEEG) of behavior. Normative developmental vEEG data in control animals are fundamental for the study of abnormal background activity in animal models of seizures or other neurologic disorders. Electrical recordings from immature, freely behaving rodents can be particularly difficult because of the small size of immature rodents, their thin and soft skull, interference with the recording apparatus by the dam, and other technical challenges. In this report of the TASK1 Working Group 2 (WG2) of the International League Against Epilepsy/American Epilepsy Society (ILAE/AES) Joint Translational Task Force, we provide suggestions that aim to optimize future vEEG recordings from immature rodents, as well as their interpretation. We focus on recordings from immature rodents younger than 30 days old used as experimental controls, because the quality and correct interpretation of such recordings is important when interpreting the vEEG results of animals serving as models of neurologic disorders. We discuss the technical aspects of such recordings and compare tethered versus wireless approaches. We also summarize the appearance of common artifacts and various patterns of electrical activity seen in young rodents used as controls as a function of behavioral state, age, and (where known) sex and strain. The information herein will hopefully help improve the methodology of vEEG recordings from immature rodents and may lead to results and interpretations that are more consistent across studies from different laboratories.
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Affiliation(s)
- Ozlem Akman
- Department of Physiology Faculty of Medicine Istanbul Bilim University Istanbul Turkey
| | - Yogendra H Raol
- Division of Neurology Department of Pediatrics School of Medicine Translational Epilepsy Research Program University of Colorado Aurora Colorado U.S.A
| | - Stéphane Auvin
- PROTECT, INSERM UMR1141 APHP University Paris Diderot Sorbonne Paris Cité Paris France.,University Hospital Robert-Debré Service of Pediatric Neurology Paris France
| | - Miguel A Cortez
- Department of Pediatrics University of Toronto Toronto Ontario Canada.,Program of Neurosciences and Mental Health Peter Gilgan Center for Research and Learning SickKids Research Institute Toronto Ontario Canada.,Division of Neurology The Hospital for Sick Children Toronto Ontario Canada
| | - Hana Kubova
- Department of Developmental Epileptology Institute of the Czech Academy of Sciences Czech Academy of Sciences Prague Czech Republic
| | - Marco de Curtis
- Epilepsy Unit Carlo Besta Neurological Institute Foundation Milan Italy
| | - Akio Ikeda
- Department of Epilepsy, Movement Disorders, and Physiology Kyoto University Graduate School of Medicine Kyoto Japan
| | - F Edward Dudek
- Department of Neurosurgery University of Utah School of Medicine Salt Lake City Utah U.S.A
| | - Aristea S Galanopoulou
- Laboratory of Developmental Epilepsy Saul R. Korey Department of Neurology Dominick P. Purpura Department of Neuroscience Isabelle Rapin Division of Child Neurology Albert Einstein College of Medicine Einstein/Montefiore Epilepsy Center Montefiore Medical Center Bronx New York U.S.A
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Ben-Ari Y. Oxytocin and Vasopressin, and the GABA Developmental Shift During Labor and Birth: Friends or Foes? Front Cell Neurosci 2018; 12:254. [PMID: 30186114 PMCID: PMC6110879 DOI: 10.3389/fncel.2018.00254] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 07/24/2018] [Indexed: 12/15/2022] Open
Abstract
Oxytocin (OT) and vasopressin (AVP) are usually associated with sociability and reduced stress for the former and antidiuretic agent associated with severe stress and pathological conditions for the latter. Both OT and AVP play major roles during labor and birth. Recent contradictory studies suggest that they might exert different roles on the GABA excitatory/inhibitory developmental shift. We reported (Tyzio et al., 2006) that at birth, OT exerts a neuro-protective action mediated by an abrupt reduction of intracellular chloride levels ([Cl-]i) that are high in utero, reinforcing GABAergic inhibition and modulating the generation of the first synchronized patterns of cortical networks. This reduction of [Cl-]i levels is abolished in rodent models of Fragile X Syndrome and Autism Spectrum Disorders, and its restoration attenuates the severity of the pathological sequels, stressing the importance of the shift at birth (Tyzio et al., 2014). In contrast, Kaila and co-workers (Spoljaric et al., 2017) reported excitatory GABA actions before and after birth that are modulated by AVP but not by OT, challenging both the developmental shift and the roles of OT. Here, I analyze the differences between these studies and suggest that the ratio AVP/OT like that of excitatory/inhibitory GABA depend on stress and pathological conditions.
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Affiliation(s)
- Yehezkel Ben-Ari
- Neurochlore and Ben-Ari Institute of Neuroarcheology (IBEN), Marseille, France
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Khazipov R, Milh M. Early patterns of activity in the developing cortex: Focus on the sensorimotor system. Semin Cell Dev Biol 2018; 76:120-129. [DOI: 10.1016/j.semcdb.2017.09.014] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 09/07/2017] [Accepted: 09/08/2017] [Indexed: 02/08/2023]
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Lebedeva J, Zakharov A, Ogievetsky E, Minlebaeva A, Kurbanov R, Gerasimova E, Sitdikova G, Khazipov R. Inhibition of Cortical Activity and Apoptosis Caused by Ethanol in Neonatal Rats In Vivo. Cereb Cortex 2018; 27:1068-1082. [PMID: 26646511 DOI: 10.1093/cercor/bhv293] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Alcohol consumption during pregnancy causes fetal alcohol spectrum disorder, which includes neuroapoptosis and neurobehavioral deficits. The neuroapoptotic effects of alcohol have been hypothesized to involve suppression of brain activity. However, in vitro studies suggest that ethanol acts as a potent stimulant of cortical activity. We explored the effects of alcohol (1-6 g/kg) on electrical activity in the rat somatosensory cortex in vivo at postnatal days P1-23 and compared them with its apoptotic actions. At P4-7, when the peak of alcohol-induced apoptosis was observed, alcohol strongly suppressed spontaneous gamma and spindle-bursts and almost completely silenced neurons in a dose-dependent manner. The dose-dependence of suppression of neuronal activity strongly correlated with the alcohol-induced neuroapoptosis. Alcohol also profoundly inhibited sensory-evoked bursts and suppressed motor activity, a physiological trigger of cortical activity bursts in newborns. The suppressive effects of ethanol on neuronal activity waned during the second and third postnatal weeks, when instead of silencing the cortex, alcohol evoked delta-wave electrographic activity. Thus, the effects of alcohol on brain activity are strongly age-dependent, and during the first postnatal week alcohol profoundly inhibits brain activity. Our findings suggest that the adverse effects of alcohol in the developing brain involve suppression of neuronal activity.
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Affiliation(s)
- Julia Lebedeva
- Laboratory of Neurobiology, Kazan Federal University, Kazan, 420000, Russia.,INMED, INSERM U-901, Marseille, 13273, France.,Aix-Marseille University, Marseille, 13273, France
| | - Andrei Zakharov
- Laboratory of Neurobiology, Kazan Federal University, Kazan, 420000, Russia.,Department of Physiology, Kazan State Medical University, Kazan, 420012, Russia
| | - Elena Ogievetsky
- INMED, INSERM U-901, Marseille, 13273, France.,Aix-Marseille University, Marseille, 13273, France
| | - Alina Minlebaeva
- INMED, INSERM U-901, Marseille, 13273, France.,Aix-Marseille University, Marseille, 13273, France
| | - Rustem Kurbanov
- Laboratory of Neurobiology, Kazan Federal University, Kazan, 420000, Russia
| | - Elena Gerasimova
- Laboratory of Neurobiology, Kazan Federal University, Kazan, 420000, Russia
| | - Guzel Sitdikova
- Laboratory of Neurobiology, Kazan Federal University, Kazan, 420000, Russia
| | - Roustem Khazipov
- Laboratory of Neurobiology, Kazan Federal University, Kazan, 420000, Russia.,INMED, INSERM U-901, Marseille, 13273, France.,Aix-Marseille University, Marseille, 13273, France
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Blanquie O, Yang JW, Kilb W, Sharopov S, Sinning A, Luhmann HJ. Electrical activity controls area-specific expression of neuronal apoptosis in the mouse developing cerebral cortex. eLife 2017; 6:27696. [PMID: 28826501 PMCID: PMC5582867 DOI: 10.7554/elife.27696] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 08/18/2017] [Indexed: 12/22/2022] Open
Abstract
Programmed cell death widely but heterogeneously affects the developing brain, causing the loss of up to 50% of neurons in rodents. However, whether this heterogeneity originates from neuronal identity and/or network-dependent processes is unknown. Here, we report that the primary motor cortex (M1) and primary somatosensory cortex (S1), two adjacent but functionally distinct areas, display striking differences in density of apoptotic neurons during the early postnatal period. These differences in rate of apoptosis negatively correlate with region-dependent levels of activity. Disrupting this activity either pharmacologically or by electrical stimulation alters the spatial pattern of apoptosis and sensory deprivation leads to exacerbated amounts of apoptotic neurons in the corresponding functional area of the neocortex. Thus, our data demonstrate that spontaneous and periphery-driven activity patterns are important for the structural and functional maturation of the neocortex by refining the final number of cortical neurons in a region-dependent manner.
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Affiliation(s)
- Oriane Blanquie
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Jenq-Wei Yang
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Werner Kilb
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Salim Sharopov
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Anne Sinning
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Heiko J Luhmann
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
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Lotfullina N, Khazipov R. Ethanol and the Developing Brain: Inhibition of Neuronal Activity and Neuroapoptosis. Neuroscientist 2017; 24:130-141. [PMID: 28580823 DOI: 10.1177/1073858417712667] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Ethanol induces massive neuroapoptosis in the developing brain. One of the main hypotheses that has been put forward to explain the deleterious actions of ethanol in the immature brain involves an inhibition of neuronal activity. Here, we review recent evidence for this hypothesis obtained in the somatosensory cortex and hippocampus of neonatal rodents. In both structures, ethanol strongly inhibits brain activity. At the doses inducing massive neuroapoptosis, ethanol completely suppresses the early activity patterns of spindle-bursts and gamma oscillations in the neocortex and the early sharp-waves in the hippocampus. The inhibitory effects of ethanol decrease with age and in adult animals, ethanol only mildly depresses neuronal firing and induces delta-wave activity. Suppression of cortical activity in neonatal animals likely involves inhibition of the myoclonic twitches, an important physiological trigger for the early activity bursts, and inhibition of the thalamocortical and intracortical circuits through a potentiation of GABAergic transmission and an inhibition of N-methyl-d-aspartate (NMDA) receptors, that is in keeping with the neuroapoptotic effects of other agents acting on GABA and NMDA receptors. These findings provide support for the hypothesis that the ethanol-induced inhibition of cortical activity is an important pathophysiological mechanism underlying massive neuroapoptosis induced by ethanol in the developing brain.
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Affiliation(s)
- Nailya Lotfullina
- 1 INMED-INSERM, Aix-Marseille University, Marseille, France.,2 Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia
| | - Roustem Khazipov
- 1 INMED-INSERM, Aix-Marseille University, Marseille, France.,2 Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia
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Milanovic D, Pesic V, Loncarevic-Vasiljkovic N, Avramovic V, Tesic V, Jevtovic-Todorovic V, Kanazir S, Ruzdijic S. Neonatal Propofol Anesthesia Changes Expression of Synaptic Plasticity Proteins and Increases Stereotypic and Anxyolitic Behavior in Adult Rats. Neurotox Res 2017; 32:247-263. [DOI: 10.1007/s12640-017-9730-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 03/28/2017] [Accepted: 04/04/2017] [Indexed: 10/19/2022]
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Cornelissen L, Bergin AM, Lobo K, Donado C, Soul JS, Berde CB. Electroencephalographic discontinuity during sevoflurane anesthesia in infants and children. Paediatr Anaesth 2017; 27:251-262. [PMID: 28177176 DOI: 10.1111/pan.13061] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/31/2016] [Indexed: 11/27/2022]
Abstract
BACKGROUND Deep anesthesia in adults may be associated with electroencephalographic (EEG) suppression and higher rates of postoperative complications. Little is known about the impact of anesthetic depth on short- or long-term outcomes in pediatrics. Brain activity monitoring may complement clinical signs of anesthetic depth. This prospective observational study aimed to assess the frequency and degree of profound EEG suppression using multichannel EEG in children during sevoflurane general anesthesia. METHODS Children aged 0-40 months who required general anesthesia for elective surgery were included. Continuous EEG recordings were performed starting from when anesthesia began and until recovery. Discontinuity was defined as EEG amplitude <25 uV, lasting ≥2 s, and observed in all electrodes across the scalp. Frequency, duration, and inter-event interval of discontinuity events were measured. Relationships between discontinuity events and postnatal age, endtidal sevoflurane concentration (etSEVO), and multiple clinical parameters were analyzed. RESULTS Discontinuity events were observed in 35/68 children, with a median duration of 10 s (95%CI: 8-12) and a median of 4 events per patient (95%CI: 2-7). Children who had discontinuity events were younger (5.5 months, 95%CI: 3.6-6.5) compared to children who did not have discontinuity events (10.2 months, 95%CI: 6.1-14); (difference between medians, 4.7 months, 95%CI: 2.3-8, P = 0.0002). Younger infants exhibited a higher number of discontinuity events, and the incidence decreased with postnatal age (r68 = -0.53, P < 0.0001). The majority of discontinuity events were observed during the first 30 min of anesthesia (66.4% total events), where etSEVO was >3%. Few discontinuity events were observed during maintenance and none during emergence. Blood pressure, heart rate, tissue oxygen saturation, and endtidal CO2 partial pressure did not change during these events. CONCLUSIONS Electroencephalographic monitoring may complement clinical signs in providing information about brain homeostasis during general anesthesia. The impact of discontinuity events on immediate and long-term outcomes merits further study.
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Affiliation(s)
- Laura Cornelissen
- Department of Anesthesiology, Perioperative & Pain Medicine, Boston Children's Hospital, Boston, MA, USA.,Department of Anaesthesia, Harvard Medical School, Boston, MA, USA
| | - Ann M Bergin
- Department of Neurology, Boston Children's Hospital, Boston, MA, USA.,Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Kimberly Lobo
- Department of Anesthesiology, Perioperative & Pain Medicine, Boston Children's Hospital, Boston, MA, USA.,Department of Anaesthesia, Harvard Medical School, Boston, MA, USA
| | - Carolina Donado
- Department of Anesthesiology, Perioperative & Pain Medicine, Boston Children's Hospital, Boston, MA, USA.,Department of Anaesthesia, Harvard Medical School, Boston, MA, USA
| | - Janet S Soul
- Department of Neurology, Boston Children's Hospital, Boston, MA, USA.,Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Charles B Berde
- Department of Anesthesiology, Perioperative & Pain Medicine, Boston Children's Hospital, Boston, MA, USA.,Department of Anaesthesia, Harvard Medical School, Boston, MA, USA
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34
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Tan HM, Wills TJ, Cacucci F. The development of spatial and memory circuits in the rat. WILEY INTERDISCIPLINARY REVIEWS. COGNITIVE SCIENCE 2016. [DOI: 10.10.1002/wcs.1424] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Hui Min Tan
- Singapore Institute for Clinical SciencesSingapore
| | - Thomas Joseph Wills
- Department of Cell and Developmental Biology, Division of BiosciencesUniversity College LondonLondonUK
| | - Francesca Cacucci
- Department of Neuroscience, Physiology and Pharmacology, Division of BiosciencesUniversity College LondonLondonUK
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35
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Tan HM, Wills TJ, Cacucci F. The development of spatial and memory circuits in the rat. WILEY INTERDISCIPLINARY REVIEWS. COGNITIVE SCIENCE 2016; 8. [DOI: 10.1002/wcs.1424] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2016] [Revised: 09/12/2016] [Accepted: 09/16/2016] [Indexed: 12/19/2022]
Affiliation(s)
- Hui Min Tan
- Singapore Institute for Clinical SciencesSingapore
| | - Thomas Joseph Wills
- Department of Cell and Developmental Biology, Division of BiosciencesUniversity College LondonLondonUK
| | - Francesca Cacucci
- Department of Neuroscience, Physiology and Pharmacology, Division of BiosciencesUniversity College LondonLondonUK
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36
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Chang P, Fabrizi L, Olhede S, Fitzgerald M. The Development of Nociceptive Network Activity in the Somatosensory Cortex of Freely Moving Rat Pups. Cereb Cortex 2016; 26:4513-4523. [PMID: 27797835 PMCID: PMC5193146 DOI: 10.1093/cercor/bhw330] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 10/02/2016] [Indexed: 12/13/2022] Open
Abstract
Cortical perception of noxious stimulation is an essential component of pain experience but it is not known how cortical nociceptive activity emerges during brain development. Here we use continuous telemetric electrocorticogram (ECoG) recording from the primary somatosensory cortex (S1) of awake active rat pups to map functional nociceptive processing in the developing brain over the first 4 weeks of life. Cross-sectional and longitudinal recordings show that baseline S1 ECoG energy increases steadily with age, with a distinctive beta component replaced by a distinctive theta component in week 3. Event-related potentials were evoked by brief noxious hindpaw skin stimulation at all ages tested, confirming the presence of functional nociceptive spinothalamic inputs in S1. However, hindpaw incision, which increases pain sensitivity at all ages, did not increase S1 ECoG energy until week 3. A significant increase in gamma (20–50 Hz) energy occurred in the presence of skin incision at week 3 accompanied by a longer-lasting increase in theta (4–8 Hz) energy at week 4. Continuous ECoG recording demonstrates specific postnatal functional stages in the maturation of S1 cortical nociception. Somatosensory cortical coding of an ongoing pain “state” in awake rat pups becomes apparent between 2 and 4 weeks of age.
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Affiliation(s)
- P Chang
- Department of Neuroscience, Physiology & Pharmacology, University College London, London WC1E6BT, UK.,Current address: Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London WC1N 3BG, UK
| | - L Fabrizi
- Department of Neuroscience, Physiology & Pharmacology, University College London, London WC1E6BT, UK
| | - S Olhede
- Department of Statistical Science, University College London, London WC1E6BT, UK
| | - M Fitzgerald
- Department of Neuroscience, Physiology & Pharmacology, University College London, London WC1E6BT, UK
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37
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Differential Suppression of Spontaneous and Noxious-evoked Somatosensory Cortical Activity by Isoflurane in the Neonatal Rat. Anesthesiology 2016; 124:885-98. [PMID: 26808637 DOI: 10.1097/aln.0000000000001017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
BACKGROUND The effect of neonatal anesthesia and pain on the developing brain is of considerable clinical importance, but few studies have evaluated noxious surgical input to the infant brain under anesthesia. Herein, the authors tested the effect of increasing isoflurane concentration on spontaneous and evoked nociceptive activity in the somatosensory cortex of rats at different postnatal ages. METHODS Intracortical extracellular field potentials evoked by hind paw C-fiber electrical stimulation were recorded in the rat somatosensory cortex at postnatal day (P) 7, P14, P21, and P30 during isoflurane anesthesia (n = 7 per group). The amplitudes of evoked potentials and the energies of evoked oscillations (1 to 100 Hz over 3 s) were measured after equilibration at 1.5% isoflurane and during step increases in inspired isoflurane. Responses during and after plantar hind paw incision were compared at P7 and P30 (n = 6 per group). RESULTS At P7, cortical activity was silent at 1.5% isoflurane but noxious-evoked potentials decreased only gradually in amplitude and energy with step increases in isoflurane. The resistance of noxious-evoked potentials to isoflurane at P7 was significantly enhanced after surgical hind paw incision (69 ± 16% vs. 6 ± 1% in nonincised animals at maximum inspired isoflurane). This resistance was age dependent; at P14 to P30, noxious-evoked responses decreased sharply with increasing isoflurane (step 3 [4%] P7: 50 ± 9%, P30: 4 ± 1% of baseline). Hind paw incision at P30 sensitized noxious-evoked potentials, but this was suppressed by higher isoflurane concentrations. CONCLUSIONS Despite suppression of spontaneous activity, cortical-evoked potentials are more resistant to isoflurane in young rats and are further sensitized by surgical injury.
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Lebedeva YA, Zakharova AV, Sitdikova GF, Zefirov AL, Khazipov RN. Ketamine-Midazolam Anesthesia Induces Total Inhibition of Cortical Activity in the Brain of Newborn Rats. Bull Exp Biol Med 2016; 161:15-9. [PMID: 27270941 DOI: 10.1007/s10517-016-3334-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Indexed: 11/25/2022]
Abstract
The effects of general anesthetics ketamine and midazolam, the drugs that cause neuroapoptosis at the early stages of CNS development, on electrical activity of the somatosensory cortex in newborn rats were studied using extracellular recording of local field potentials and action potentials of cortical neurons. Combined administration of ketamine (40 mg/kg) and midazolam (9 mg/kg) induced surgical coma and almost completely suppressed early oscillatory patterns and neuronal firing. These effects persisted over 3 h after injection of the anesthetics. We concluded that general anesthesia induced by combined administration of ketamine and midazolam profoundly suppressed cortical activity in newborn rats, which can trigger neuroapoptosis in the developing brain.
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Affiliation(s)
- Yu A Lebedeva
- Kazan (Volga Region) Federal University, Kazan, Russia.,Mediterranean Institute of Neurobiology (INMED), Marseille, France
| | - A V Zakharova
- Kazan (Volga Region) Federal University, Kazan, Russia.,Kazan State Medical University, Ministry of Health of the Russian Federation, Kazan, Tatarstan Republic, Russia
| | - G F Sitdikova
- Kazan (Volga Region) Federal University, Kazan, Russia
| | - A L Zefirov
- Kazan State Medical University, Ministry of Health of the Russian Federation, Kazan, Tatarstan Republic, Russia
| | - R N Khazipov
- Kazan (Volga Region) Federal University, Kazan, Russia. .,Mediterranean Institute of Neurobiology (INMED), Marseille, France. .,Aix-Marseille University, Marseille, France.
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40
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Lissek T, Obenhaus HA, Ditzel DAW, Nagai T, Miyawaki A, Sprengel R, Hasan MT. General Anesthetic Conditions Induce Network Synchrony and Disrupt Sensory Processing in the Cortex. Front Cell Neurosci 2016; 10:64. [PMID: 27147963 PMCID: PMC4830828 DOI: 10.3389/fncel.2016.00064] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 02/29/2016] [Indexed: 12/19/2022] Open
Abstract
General anesthetics are commonly used in animal models to study how sensory signals are represented in the brain. Here, we used two-photon (2P) calcium activity imaging with cellular resolution to investigate how neuronal activity in layer 2/3 of the mouse barrel cortex is modified under the influence of different concentrations of chemically distinct general anesthetics. Our results show that a high isoflurane dose induces synchrony in local neuronal networks and these cortical activity patterns closely resemble those observed in EEG recordings under deep anesthesia. Moreover, ketamine and urethane also induced similar activity patterns. While investigating the effects of deep isoflurane anesthesia on whisker and auditory evoked responses in the barrel cortex, we found that dedicated spatial regions for sensory signal processing become disrupted. We propose that our isoflurane-2P imaging paradigm can serve as an attractive model system to dissect cellular and molecular mechanisms that induce the anesthetic state, and it might also provide important insight into sleep-like brain states and consciousness.
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Affiliation(s)
- Thomas Lissek
- Department of Molecular Neurobiology, Max Planck Institute for Medical ResearchHeidelberg, Germany; Department of Neurobiology, Interdisciplinary Center for Neurosciences, University of HeidelbergHeidelberg, Germany
| | - Horst A Obenhaus
- Department of Molecular Neurobiology, Max Planck Institute for Medical Research Heidelberg, Germany
| | - Désirée A W Ditzel
- Department of Molecular Neurobiology, Max Planck Institute for Medical ResearchHeidelberg, Germany; Max Planck Research Group at the Institute for Anatomy and Cell Biology, Heidelberg UniversityHeidelberg, Germany
| | - Takeharu Nagai
- Laboratory for Nanosystems Physiology, Hokkaido University Hokkaido, Japan
| | - Atsushi Miyawaki
- RIKEN-Brain Science Institute, Laboratory for Cell Function Dynamics Saitama, Japan
| | - Rolf Sprengel
- Department of Molecular Neurobiology, Max Planck Institute for Medical ResearchHeidelberg, Germany; Max Planck Research Group at the Institute for Anatomy and Cell Biology, Heidelberg UniversityHeidelberg, Germany
| | - Mazahir T Hasan
- Department of Molecular Neurobiology, Max Planck Institute for Medical ResearchHeidelberg, Germany; Molecular Neurobiology, Neurocure Cluster of Excellence, Charite-UniversitätsmedizinBerlin, Germany
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Valiullina F, Akhmetshina D, Nasretdinov A, Mukhtarov M, Valeeva G, Khazipov R, Rozov A. Developmental Changes in Electrophysiological Properties and a Transition from Electrical to Chemical Coupling between Excitatory Layer 4 Neurons in the Rat Barrel Cortex. Front Neural Circuits 2016; 10:1. [PMID: 26834567 PMCID: PMC4720737 DOI: 10.3389/fncir.2016.00001] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 01/02/2016] [Indexed: 11/22/2022] Open
Abstract
During development, sensory systems switch from an immature to an adult mode of function along with the emergence of the active cortical states. Here, we used patch-clamp recordings from neocortical slices in vitro to characterize the developmental changes in the basic electrophysiological properties of excitatory L4 neurons and their connectivity before and after the developmental switch, which occurs in the rat barrel cortex in vivo at postnatal day P8. Prior to the switch, L4 neurons had higher resting membrane potentials, higher input resistance, lower membrane capacity, as well as action potentials (APs) with smaller amplitudes, longer durations and higher AP thresholds compared to the neurons after the switch. A sustained firing pattern also emerged around the switch. Dual patch-clamp recordings from L4 neurons revealed that recurrent connections between L4 excitatory cells do not exist before and develop rapidly across the switch. In contrast, electrical coupling between these neurons waned around the switch. We suggest that maturation of electrophysiological features, particularly acquisition of a sustained firing pattern, and a transition from the immature electrical to mature chemical synaptic coupling between excitatory L4 neurons, contributes to the developmental switch in the cortical mode of function.
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Affiliation(s)
- Fliza Valiullina
- Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University Kazan, Russia
| | - Dinara Akhmetshina
- Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University Kazan, Russia
| | - Azat Nasretdinov
- Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University Kazan, Russia
| | - Marat Mukhtarov
- Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University Kazan, Russia
| | - Guzel Valeeva
- Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University Kazan, Russia
| | - Roustem Khazipov
- Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal UniversityKazan, Russia; Institut de Neurobiologie de la Méditerranée, Institut National de la Santé et de la Recherche Médicale UMR901Marseille, France; Aix-Marseille UniversityMarseille, France
| | - Andrei Rozov
- Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal UniversityKazan, Russia; Department of Physiology and Pathophysiology, University of HeidelbergHeidelberg, Germany
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Noda T, Takahashi H. Anesthetic effects of isoflurane on the tonotopic map and neuronal population activity in the rat auditory cortex. Eur J Neurosci 2015; 42:2298-311. [PMID: 26118739 DOI: 10.1111/ejn.13007] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Revised: 06/23/2015] [Accepted: 06/24/2015] [Indexed: 12/01/2022]
Abstract
Since its discovery nearly four decades ago, sequential microelectrode mapping using hundreds of recording sites has been able to reveal a precise tonotopic organization of the auditory cortex. Despite concerns regarding the effects that anesthesia might have on neuronal responses to tones, anesthesia was essential for these experiments because such dense mapping was elaborate and time-consuming. Here, taking an 'all-at-once' approach, we investigated how isoflurane modifies spatiotemporal activities by using a dense microelectrode array. The array covered the entire auditory cortex in rats, including the core and belt cortices. By comparing neuronal activity in the awake state with activity under isoflurane anesthesia, we made four observations. First, isoflurane anesthesia did not modify the tonotopic topography within the auditory cortex. Second, in terms of general response properties, isoflurane anesthesia decreased the number of active single units and increased their response onset latency. Third, in terms of tuning properties, isoflurane anesthesia shifted the response threshold without changing the shape of the frequency response area and decreased the response quality. Fourth, in terms of population activities, isoflurane anesthesia increased the noise correlations in discharges and phase synchrony in local field potential (LFP) oscillations, suggesting that the anesthesia made neuronal activities redundant at both single-unit and LFP levels. Thus, while isoflurane anesthesia had little effect on the tonotopic topography, its profound effects on neuronal activities decreased the encoding capacity of the auditory cortex.
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Affiliation(s)
- Takahiro Noda
- Research Center for Advanced Science and Technology, The University of Tokyo, Komaba 4-6-1, Meguro-ku, Tokyo, 153-8904, Japan
| | - Hirokazu Takahashi
- Research Center for Advanced Science and Technology, The University of Tokyo, Komaba 4-6-1, Meguro-ku, Tokyo, 153-8904, Japan.,PRESTO, JST, Kawaguchi, Saitama, Japan
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Bojak I, Stoyanov ZV, Liley DTJ. Emergence of spatially heterogeneous burst suppression in a neural field model of electrocortical activity. Front Syst Neurosci 2015; 9:18. [PMID: 25767438 PMCID: PMC4341547 DOI: 10.3389/fnsys.2015.00018] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Accepted: 02/02/2015] [Indexed: 11/17/2022] Open
Abstract
Burst suppression in the electroencephalogram (EEG) is a well-described phenomenon that occurs during deep anesthesia, as well as in a variety of congenital and acquired brain insults. Classically it is thought of as spatially synchronous, quasi-periodic bursts of high amplitude EEG separated by low amplitude activity. However, its characterization as a “global brain state” has been challenged by recent results obtained with intracranial electrocortigraphy. Not only does it appear that burst suppression activity is highly asynchronous across cortex, but also that it may occur in isolated regions of circumscribed spatial extent. Here we outline a realistic neural field model for burst suppression by adding a slow process of synaptic resource depletion and recovery, which is able to reproduce qualitatively the empirically observed features during general anesthesia at the whole cortex level. Simulations reveal heterogeneous bursting over the model cortex and complex spatiotemporal dynamics during simulated anesthetic action, and provide forward predictions of neuroimaging signals for subsequent empirical comparisons and more detailed characterization. Because burst suppression corresponds to a dynamical end-point of brain activity, theoretically accounting for its spatiotemporal emergence will vitally contribute to efforts aimed at clarifying whether a common physiological trajectory is induced by the actions of general anesthetic agents. We have taken a first step in this direction by showing that a neural field model can qualitatively match recent experimental data that indicate spatial differentiation of burst suppression activity across cortex.
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Affiliation(s)
- Ingo Bojak
- Systems Neuroscience Research Group, School of Systems Engineering, University of Reading Reading, UK
| | - Zhivko V Stoyanov
- Systems Neuroscience Research Group, School of Systems Engineering, University of Reading Reading, UK
| | - David T J Liley
- Brain and Psychological Sciences Research Centre, School of Health Sciences, Swinburne University of Technology Hawthorn, VIC, Australia
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Kislin M, Mugantseva E, Molotkov D, Kulesskaya N, Khirug S, Kirilkin I, Pryazhnikov E, Kolikova J, Toptunov D, Yuryev M, Giniatullin R, Voikar V, Rivera C, Rauvala H, Khiroug L. Flat-floored air-lifted platform: a new method for combining behavior with microscopy or electrophysiology on awake freely moving rodents. J Vis Exp 2014:e51869. [PMID: 24998224 PMCID: PMC4209781 DOI: 10.3791/51869] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
It is widely acknowledged that the use of general anesthetics can undermine the relevance of electrophysiological or microscopical data obtained from a living animal’s brain. Moreover, the lengthy recovery from anesthesia limits the frequency of repeated recording/imaging episodes in longitudinal studies. Hence, new methods that would allow stable recordings from non-anesthetized behaving mice are expected to advance the fields of cellular and cognitive neurosciences. Existing solutions range from mere physical restraint to more sophisticated approaches, such as linear and spherical treadmills used in combination with computer-generated virtual reality. Here, a novel method is described where a head-fixed mouse can move around an air-lifted mobile homecage and explore its environment under stress-free conditions. This method allows researchers to perform behavioral tests (e.g., learning, habituation or novel object recognition) simultaneously with two-photon microscopic imaging and/or patch-clamp recordings, all combined in a single experiment. This video-article describes the use of the awake animal head fixation device (mobile homecage), demonstrates the procedures of animal habituation, and exemplifies a number of possible applications of the method.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Rashid Giniatullin
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland
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Cichon NB, Denker M, Grün S, Hanganu-Opatz IL. Unsupervised classification of neocortical activity patterns in neonatal and pre-juvenile rodents. Front Neural Circuits 2014; 8:50. [PMID: 24904296 PMCID: PMC4034041 DOI: 10.3389/fncir.2014.00050] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Accepted: 04/24/2014] [Indexed: 11/13/2022] Open
Abstract
Flexible communication within the brain, which relies on oscillatory activity, is not confined to adult neuronal networks. Experimental evidence has documented the presence of discontinuous patterns of oscillatory activity already during early development. Their highly variable spatial and time-frequency organization has been related to region specificity. However, it might be equally due to the absence of unitary criteria for classifying the early activity patterns, since they have been mainly characterized by visual inspection. Therefore, robust and unbiased methods for categorizing these discontinuous oscillations are needed for increasingly complex data sets from different labs. Here, we introduce an unsupervised detection and classification algorithm for the discontinuous activity patterns of rodents during early development. For this, in a first step time windows with discontinuous oscillations vs. epochs of network “silence” were identified. In a second step, the major features of detected events were identified and processed by principal component analysis for deciding on their contribution to the classification of different oscillatory patterns. Finally, these patterns were categorized using an unsupervised cluster algorithm. The results were validated on manually characterized neonatal spindle bursts (SB), which ubiquitously entrain neocortical areas of rats and mice, and prelimbic nested gamma spindle bursts (NG). Moreover, the algorithm led to satisfactory results for oscillatory events that, due to increased similarity of their features, were more difficult to classify, e.g., during the pre-juvenile developmental period. Based on a linear classification, the optimal number of features to consider increased with the difficulty of detection. This algorithm allows the comparison of neonatal and pre-juvenile oscillatory patterns in their spatial and temporal organization. It might represent a first step for the unbiased elucidation of activity patterns during development.
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Affiliation(s)
- Nicole B Cichon
- Developmental Neurophysiology, Neuroanatomy, University Medical Center Hamburg-Eppendorf Hamburg, Germany
| | - Michael Denker
- Institute of Neuroscience and Medicine (INM-6) and Institute for Advanced Simulation (IAS-6), Jülich Research Centre and JARA Jülich, Germany
| | - Sonja Grün
- Institute of Neuroscience and Medicine (INM-6) and Institute for Advanced Simulation (IAS-6), Jülich Research Centre and JARA Jülich, Germany ; Theoretical Systems Neurobiology, RWTH Aachen University Aachen, Germany ; RIKEN Brain Science Institute Wako-shi, Saitama, Japan
| | - Ileana L Hanganu-Opatz
- Developmental Neurophysiology, Neuroanatomy, University Medical Center Hamburg-Eppendorf Hamburg, Germany
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