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Mondino A, González J, Li D, Mateos D, Osorio L, Cavelli M, Castro-Nin JP, Serantes D, Costa A, Vanini G, Mashour GA, Torterolo P. Urethane anaesthesia exhibits neurophysiological correlates of unconsciousness and is distinct from sleep. Eur J Neurosci 2024; 59:483-501. [PMID: 35545450 DOI: 10.1111/ejn.15690] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Revised: 04/13/2022] [Accepted: 05/06/2022] [Indexed: 11/27/2022]
Abstract
Urethane is a general anaesthetic widely used in animal research. The state of urethane anaesthesia is unique because it alternates between macroscopically distinct electrographic states: a slow-wave state that resembles non-rapid eye movement (NREM) sleep and an activated state with features of both REM sleep and wakefulness. Although it is assumed that urethane produces unconsciousness, this has been questioned because of states of cortical activation during drug exposure. Furthermore, the similarities and differences between urethane anaesthesia and physiological sleep are still unclear. In this study, we recorded the electroencephalogram (EEG) and electromyogram in chronically prepared rats during natural sleep-wake states and during urethane anaesthesia. We subsequently analysed the power, coherence, directed connectivity and complexity of brain oscillations and found that EEG under urethane anaesthesia has clear signatures of unconsciousness, with similarities to other general anaesthetics. In addition, the EEG profile under urethane is different in comparison with natural sleep states. These results suggest that consciousness is disrupted during urethane. Furthermore, despite similarities that have led others to conclude that urethane is a model of sleep, the electrocortical traits of depressed and activated states during urethane anaesthesia differ from physiological sleep states.
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Affiliation(s)
- Alejandra Mondino
- Department of Physiology, Faculty of Medicine, University of the Republic, Montevideo, Uruguay
| | - Joaquín González
- Department of Physiology, Faculty of Medicine, University of the Republic, Montevideo, Uruguay
| | - Duan Li
- Department of Anesthesiology, University of Michigan, Ann Arbor, Michigan, USA
- Center for Consciousness Science, University of Michigan, Ann Arbor, Michigan, USA
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, Michigan, USA
| | - Diego Mateos
- Institute of Applied Mathematics of the Coast-CONICET-UNL, CCT CONICET, Santa Fe, Argentina
- Faculty of Science and Technology, Autonomous University of Entre Ríos, Parana, Argentina
| | - Lucía Osorio
- Department of Physiology, Faculty of Medicine, University of the Republic, Montevideo, Uruguay
| | - Matías Cavelli
- Department of Physiology, Faculty of Medicine, University of the Republic, Montevideo, Uruguay
- Department of Psychiatry, University of Wisconsin, Madison, Wisconsin, USA
| | - Juan Pedro Castro-Nin
- Department of Physiology, Faculty of Medicine, University of the Republic, Montevideo, Uruguay
| | - Diego Serantes
- Department of Physiology, Faculty of Medicine, University of the Republic, Montevideo, Uruguay
| | - Alicia Costa
- Department of Physiology, Faculty of Medicine, University of the Republic, Montevideo, Uruguay
| | - Giancarlo Vanini
- Department of Anesthesiology, University of Michigan, Ann Arbor, Michigan, USA
- Center for Consciousness Science, University of Michigan, Ann Arbor, Michigan, USA
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, Michigan, USA
| | - George A Mashour
- Department of Anesthesiology, University of Michigan, Ann Arbor, Michigan, USA
- Center for Consciousness Science, University of Michigan, Ann Arbor, Michigan, USA
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, Michigan, USA
| | - Pablo Torterolo
- Department of Physiology, Faculty of Medicine, University of the Republic, Montevideo, Uruguay
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Loison V, Voskobiynyk Y, Lindquist B, Necula D, Longrois D, Paz J, Holcman D. Mapping general anesthesia states based on electro-encephalogram transition phases. Neuroimage 2024; 285:120498. [PMID: 38135170 PMCID: PMC10792552 DOI: 10.1016/j.neuroimage.2023.120498] [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: 05/17/2023] [Revised: 12/08/2023] [Accepted: 12/11/2023] [Indexed: 12/24/2023] Open
Abstract
Cortical electro-encephalography (EEG) served as the clinical reference for monitoring unconsciousness during general anesthesia. The existing EEG-based monitors classified general anesthesia states as underdosed, adequate, or overdosed, lacking predictive power due to the absence of transition phases among these states. In response to this limitation, we undertook an analysis of the EEG signal during isoflurane-induced general anesthesia in mice. Adopting a data-driven approach, we applied signal processing techniques to track θ- and δ-band dynamics, along with iso-electric suppressions. Combining this approach with machine learning, we successfully developed an automated algorithm. The findings of our study revealed that the dampening of the δ-band occurred several minutes before the onset of significant iso-electric suppression episodes. Furthermore, a distinct γ-frequency oscillation was observed, persisting for several minutes during the recovery phase subsequent to isoflurane-induced overdose. As a result of our research, we generated a map summarizing multiple brain states and their transitions, offering a tool for predicting and preventing overdose during general anesthesia. The transition phases identified, along with the developed algorithm, have the potential to be generalized, enabling clinicians to prevent inadequate anesthesia and, consequently, tailor anesthetic regimens to individual patients.
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Affiliation(s)
- V Loison
- Group of Data Modeling and Computational Biology, Institut de Biologie (IBENS), École Normale Supérieure CNRS, Université PSL Paris, France
| | - Y Voskobiynyk
- Gladstone Institutes, USA; Gladstone Institute of Neurological Disease, University of California, San Francisco, USA
| | - B Lindquist
- Gladstone Institutes, USA; Gladstone Institute of Neurological Disease, University of California, San Francisco, USA
| | - D Necula
- Gladstone Institutes, USA; Gladstone Institute of Neurological Disease, University of California, San Francisco, USA
| | - D Longrois
- Département d'Anesthésie-Réanimation, Hôpital Bichat-Claude Bernard, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - J Paz
- Gladstone Institutes, USA; Gladstone Institute of Neurological Disease, University of California, San Francisco, USA
| | - D Holcman
- Group of Data Modeling and Computational Biology, Institut de Biologie (IBENS), École Normale Supérieure CNRS, Université PSL Paris, France; DAMPT, University of Cambridge and Churchill College, CB30DS, Cambridge, UK.
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3
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Yang S, Xiao W, Wu H, Liu Y, Feng S, Lu J, Wang T. Management Based on Multimodal Brain Monitoring May Improve Functional Connectivity and Post-operative Neurocognition in Elderly Patients Undergoing Spinal Surgery. Front Aging Neurosci 2021; 13:705287. [PMID: 34335234 PMCID: PMC8322980 DOI: 10.3389/fnagi.2021.705287] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 06/15/2021] [Indexed: 01/11/2023] Open
Abstract
Perioperative neurocognitive disorder (PND) is a common condition in elderly patients undergoing surgery. Sedation, analgesia, regional cerebral oxygen saturation (rSO2), and body temperature are known to be associated with PND, but few studies have examined the contribution of these factors combined in detail. This prospective, randomized, controlled, double-blinded study investigated whether anesthesia management based on multimodal brain monitoring—an anesthesia management algorithm designed by our group—could improve the post-operative cognitive function and brain functional connectivity (FC) in elderly patients undergoing elective spinal surgery with general anesthesia. The patients (aged ≥65 years) were randomized into two groups [control (Group C), n = 12 and intervention (Group I), n = 14]. Patients in Group I were managed with multimodal brain monitoring (patient state index, spectral edge frequency, analgesia nociception index, rSO2, and temperature), and those in Group C were managed with routine anesthesia management. All patients were pre- and post-operatively evaluated (7 days after surgery) with the Montreal Cognitive Assessment (MoCA). Amplitude of low-frequency fluctuation (ALFF) and FC were analyzed after resting-state functional MRI. Serum C-reactive protein (CRP) and lipopolysaccharide levels were measured, and the correlation between FC and changes in inflammatory marker levels was analyzed. Mean post-operative MoCA score was higher in Group I (24.80 ± 2.09) than in Group C (22.56 ± 2.24) (p = 0.04), with no difference in PND incidence between groups (28.57 vs. 16.67%; p = 0.47). Group I also showed significantly increased ALFF values in several brain regions after surgery (p < 0.05), and FC between the left hippocampus and left orbital inferior frontal gyrus (FG), left middle FG, left superior temporal gyrus, and left precentral gyrus was enhanced (p < 0.05), which was negatively correlated with the change in serum CRP (pre vs. post-intervention) (R = −0.58, p = 0.01). These results suggest that management of elderly patients undergoing surgery by multimodal brain monitoring may improve post-operative neurocognition and FC by reducing systemic inflammation. Clinical Trial Registration:http://www.chictr.org.cn/index.aspx, identifier: ChiCTR1900028024.
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Affiliation(s)
- Shuyi Yang
- Department of Anesthesiology, Xuanwu Hospital, Capital Medical University, National Clinical Research Center for Geriatric Disease, Beijing, China
| | - Wei Xiao
- Department of Anesthesiology, Xuanwu Hospital, Capital Medical University, National Clinical Research Center for Geriatric Disease, Beijing, China
| | - Hao Wu
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Yang Liu
- Department of Anesthesiology, Xuanwu Hospital, Capital Medical University, National Clinical Research Center for Geriatric Disease, Beijing, China
| | - Shuai Feng
- Department of Anesthesiology, Xuanwu Hospital, Capital Medical University, National Clinical Research Center for Geriatric Disease, Beijing, China
| | - Jie Lu
- Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Tianlong Wang
- Department of Anesthesiology, Xuanwu Hospital, Capital Medical University, National Clinical Research Center for Geriatric Disease, Beijing, China
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Cai S, Tang AC, Luo TY, Yang SC, Yang H, Liu CX, Shu Y, Pan YC, Zhang Y, Zhou L, Yu T, Yu SY. Effect of basal forebrain somatostatin and parvalbumin neurons in propofol and isoflurane anesthesia. CNS Neurosci Ther 2021; 27:792-804. [PMID: 33764684 PMCID: PMC8193699 DOI: 10.1111/cns.13635] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 03/03/2021] [Accepted: 03/03/2021] [Indexed: 12/02/2022] Open
Abstract
Aims The basal forebrain (BF) plays an essential role in wakefulness and cognition. Two subtypes of BF gamma‐aminobutyric acid (GABA) neurons, including somatostatin‐expressing (GABASOM) and parvalbumin‐positive (GABAParv) neurons, function differently in mediating the natural sleep–wake cycle. Since the loss of consciousness induced by general anesthesia and the natural sleep–wake cycle probably share similar mechanisms, it is important to clarify the accurate roles of these neurons in general anesthesia procedure. Methods Based on two transgenic mouse lines expressing SOM‐IRES‐Cre and PV‐IRES‐Cre, we used a combination of genetic activation, inactivation, and chronic ablation approaches to further explore the behavioral and electroencephalography (EEG) roles of BFSOM and BFParv neurons in general anesthesia. After a single intravenous injection of propofol and the induction and recovery times of isoflurane anesthesia, the anesthesia time was compared. The changes in cortical EEG under different conditions were also compared. Results Activation of BF GABASOM neurons facilitates both the propofol and isoflurane anesthesia, manifesting as a longer anesthesia duration time with propofol anesthesia and a fast induction time and longer recovery time with isoflurane anesthesia. Moreover, BF GABASOM‐activated mice displayed a greater suppression of cortical electrical activity during anesthesia, showing an increase in δ power bands or a simultaneous decrease in high‐frequency power bands. However, only a limited and nuanced effect on propofol and isoflurane anesthesia was observed with the manipulated BF GABAParv neurons. Conclusions Our results suggested that BF GABASOM neurons play a critical role in propofol and isoflurane general anesthesia, while BF GABAParv neurons appeared to have little effect.
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Affiliation(s)
- Shuang Cai
- Key Laboratory of Brain Science, Zunyi Medical University, Zunyi, China
| | - Ai-Chen Tang
- Key Laboratory of Brain Science, Zunyi Medical University, Zunyi, China
| | - Tian-Yuan Luo
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi Medical University, Zunyi, China
| | - Shao-Cheng Yang
- Key Laboratory of Brain Science, Zunyi Medical University, Zunyi, China
| | - Huanhuan Yang
- Key Laboratory of Brain Science, Zunyi Medical University, Zunyi, China
| | - Cheng-Xi Liu
- Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi Medical University, Zunyi, China
| | - Yue Shu
- Key Laboratory of Brain Science, Zunyi Medical University, Zunyi, China
| | - Yun-Chao Pan
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
| | - Yu Zhang
- Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi Medical University, Zunyi, China
| | - Liang Zhou
- Key Laboratory of Brain Science, Zunyi Medical University, Zunyi, China
| | - Tian Yu
- Key Laboratory of Brain Science, Zunyi Medical University, Zunyi, China.,Department of Anesthesiology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi Medical University, Zunyi, China
| | - Shou-Yang Yu
- Key Laboratory of Brain Science, Zunyi Medical University, Zunyi, China
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Guo J, Ran M, Gao Z, Zhang X, Wang D, Li H, Zhao S, Sun W, Dong H, Hu J. Cell-type-specific imaging of neurotransmission reveals a disrupted excitatory-inhibitory cortical network in isoflurane anaesthesia. EBioMedicine 2021; 65:103272. [PMID: 33691246 PMCID: PMC7941179 DOI: 10.1016/j.ebiom.2021.103272] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 02/06/2021] [Accepted: 02/19/2021] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Despite the fundamental clinical significance of general anaesthesia, the cortical mechanism underlying anaesthetic-induced loss of consciousness (aLOC) remains elusive. METHODS Here, we measured the dynamics of two major cortical neurotransmitters, gamma-aminobutyric acid (GABA) and glutamate, through in vivo two-photon imaging and genetically encoded neurotransmitter sensors in a cell type-specific manner in the primary visual (V1) cortex. FINDINGS We found a general decrease in cortical GABA transmission during aLOC. However, the glutamate transmission varies among different cortical cell types, where in it is almost preserved on pyramidal cells and is significantly reduced on inhibitory interneurons. Cortical interneurons expressing vasoactive intestinal peptide (VIP) and parvalbumin (PV) specialize in disinhibitory and inhibitory effects, respectively. During aLOC, VIP neuronal activity was delayed, and PV neuronal activity was dramatically inhibited and highly synchronized. INTERPRETATION These data reveal that aLOC resembles a cortical state with a disrupted excitatory-inhibitory network and suggest that a functional inhibitory network is indispensable in the maintenance of consciousness. FUNDING This work was supported by the grants of the National Natural Science Foundation of China (grant nos. 81620108012 and 82030038 to H.D. and grant nos. 31922029, 61890951, and 61890950 to J.H.).
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Affiliation(s)
- Juan Guo
- Department of Anaesthesiology and Perioperative Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, China
| | - Mingzi Ran
- Department of Anaesthesiology and Perioperative Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, China
| | - Zilong Gao
- Chinese Institute for Brain Research, Beijing 102206, China
| | - Xinxin Zhang
- Chinese Institute for Brain Research, Beijing 102206, China
| | - Dan Wang
- Department of Anaesthesiology and Perioperative Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, China
| | - Huiming Li
- Department of Anaesthesiology and Perioperative Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, China
| | - Shiyi Zhao
- Department of Anaesthesiology and Perioperative Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, China
| | - Wenzhi Sun
- Chinese Institute for Brain Research, Beijing 102206, China; School of Basic Medical Sciences, Capital Medical University, Beijing 10069, China.
| | - Hailong Dong
- Department of Anaesthesiology and Perioperative Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, China.
| | - Ji Hu
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China; Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai 200030, China; Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226000, China; CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai 200030, China.
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6
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García PS, Kreuzer M, Hight D, Sleigh JW. Effects of noxious stimulation on the electroencephalogram during general anaesthesia: a narrative review and approach to analgesic titration. Br J Anaesth 2021; 126:445-457. [PMID: 33461725 DOI: 10.1016/j.bja.2020.10.036] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 10/01/2020] [Accepted: 10/24/2020] [Indexed: 01/10/2023] Open
Abstract
Electroencephalographic (EEG) activity is used to monitor the neurophysiology of the brain, which is a target organ of general anaesthesia. Besides its use in evaluating hypnotic states, neurophysiologic reactions to noxious stimulation can also be observed in the EEG. Recognising and understanding these responses could help optimise intraoperative analgesic management. This review describes three types of changes in the EEG induced by noxious stimulation when the patient is under general anaesthesia: (1) beta arousal, (2) (paradoxical) delta arousal, and (3) alpha dropout. Beta arousal is an increase in EEG power in the beta-frequency band (12-25 Hz) in response to noxious stimulation, especially at lower doses of anaesthesia drugs in the absence of opioids. It is usually indicative of a cortical depolarisation and increased cortical activity. At higher concentrations of anaesthetic drug, and with insufficient opioids, delta arousal (increased power in the delta band [0.5-4 Hz]) and alpha dropout (decreased alpha power [8-12 Hz]) are associated with noxious stimuli. The mechanisms of delta arousal are not well understood, but the midbrain reticular formation seems to play a role. Alpha dropout may indicate a return of thalamocortical communication, from an idling mode to an operational mode. Each of these EEG changes reflect an incomplete modulation of pain signals and can be mitigated by administration of opioid or the use of regional anaesthesia techniques. Future studies should evaluate whether titrating analgesic drugs in response to these EEG signals reduces postoperative pain and influences other postoperative outcomes, including the potential development of chronic pain.
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Affiliation(s)
- Paul S García
- Department of Anesthesiology, Columbia University, New York, NY, USA.
| | - Matthias Kreuzer
- Department of Anesthesiology and Intensive Care, Technical University of Munich School of Medicine, Munich, Germany
| | - Darren Hight
- Department of Anaesthesiology, Waikato Clinical School, University of Auckland, Hamilton, New Zealand; Department of Anaesthesiology and Pain Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - James W Sleigh
- Department of Anaesthesiology, Waikato Clinical School, University of Auckland, Hamilton, New Zealand
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Calderon DP, Schiff ND. Objective and graded calibration of recovery of consciousness in experimental models. Curr Opin Neurol 2021; 34:142-149. [PMID: 33278146 PMCID: PMC7866679 DOI: 10.1097/wco.0000000000000895] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE OF REVIEW Experimental preclinical models of recovery of consciousness (ROC) and anesthesia emergence are crucial for understanding the neuronal circuits restoring arousal during coma emergence. Such models can also potentially help to better understand how events during coma emergence facilitate or hinder recovery from brain injury. Here we provide an overview of current methods used to assess ROC/level of arousal in animal models. This exposes the need for objective approaches to calibrate arousal levels. We outline how correlation of measured behaviors and their reestablishment at multiple stages with cellular, local and broader neuronal networks, gives a fuller understanding of ROC. RECENT FINDINGS Animals emerging from diverse coma-like states share a dynamic process of cortical and behavioral recovery that reveals distinct states consistently sequenced from low-to-high arousal level and trackable in nonhuman primates and rodents. Neuronal activity modulation of layer V-pyramidal neurons and neuronal aggregates within the brainstem and thalamic nuclei play critical roles at specific stages to promote restoration of a conscious state. SUMMARY A comprehensive, graded calibration of cortical, physiological, and behavioral changes in animal models is undoubtedly needed to establish an integrative framework. This approach reveals the contribution of local and systemic neuronal circuits to the underlying mechanisms for recovering consciousness.
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Affiliation(s)
| | - Nicholas D Schiff
- Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, New York, USA
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Gao S, Calderon DP. Robust alternative to the righting reflex to assess arousal in rodents. Sci Rep 2020; 10:20280. [PMID: 33219247 PMCID: PMC7679463 DOI: 10.1038/s41598-020-77162-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 11/06/2020] [Indexed: 12/13/2022] Open
Abstract
The righting reflex (RR) is frequently used to assess level of arousal and applied to animal models of a range of neurological disorders. RR produces a binary result that, when positive, is used to infer restoration of consciousness, often without further behavioral corroboration. We find that RR is an unreliable metric for arousal/recovery of consciousness. Instead, cortical activity and motor behavior that accompany RR are a non-binary, superior criterion that accurately calibrates and establishes level of arousal in rodents.
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Affiliation(s)
- Sijia Gao
- Department of Anesthesiology, Weill Cornell Medical College, New York, NY, 10065, USA
- School of Electrical and Computer Engineering, Cornell University, New York, NY, 10044, USA
| | - Diany Paola Calderon
- Department of Anesthesiology, Weill Cornell Medical College, New York, NY, 10065, USA.
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Luo TY, Cai S, Qin ZX, Yang SC, Shu Y, Liu CX, Zhang Y, Zhang L, Zhou L, Yu T, Yu SY. Basal Forebrain Cholinergic Activity Modulates Isoflurane and Propofol Anesthesia. Front Neurosci 2020; 14:559077. [PMID: 33192246 PMCID: PMC7652994 DOI: 10.3389/fnins.2020.559077] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 09/22/2020] [Indexed: 11/13/2022] Open
Abstract
Cholinergic neurons in the basal forebrain (BF) have long been considered to be the key neurons in the regulation of cortical and behavioral arousal, and cholinergic activation in the downstream region of the BF can arouse anesthetized rats. However, whether the activation of BF cholinergic neurons can induce behavior and electroencephalogram (EEG) recovery from anesthesia is unclear. In this study, based on a transgenic mouse line expressing ChAT-IRES-Cre, we applied a fiber photometry system combined with GCaMPs expression in the BF and found that both isoflurane and propofol inhibit the activity of BF cholinergic neurons, which is closely related to the consciousness transition. We further revealed that genetic lesion of BF cholinergic neurons was associated with a markedly increased potency of anesthetics, while designer receptor exclusively activated by designer drugs (DREADD)-activated BF cholinergic neurons was responsible for slower induction and faster recovery of anesthesia. We also documented a significant increase in δ power bands (1-4 Hz) and a decrease in β (12-25 Hz) power bands in BF cholinergic lesioned mice, while there was a clearly noticeable decline in EEG δ power of activated BF cholinergic neurons. Moreover, sensitivity to anesthetics was reduced after optical stimulation of BF cholinergic cells, yet it failed to restore wake-like behavior in constantly anesthetized mice. Our results indicate a functional role of BF cholinergic neurons in the regulation of general anesthesia. Inhibition of BF cholinergic neurons mediates the formation of unconsciousness induced by general anesthetics, and their activation promotes recovery from the anesthesia state.
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Affiliation(s)
- Tian-Yuan Luo
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi, China
| | - Shuang Cai
- Key Laboratory of Brain Science, Zunyi Medical University, Zunyi, China
| | - Zai-Xun Qin
- Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi, China
| | - Shao-Cheng Yang
- Key Laboratory of Brain Science, Zunyi Medical University, Zunyi, China
| | - Yue Shu
- Key Laboratory of Brain Science, Zunyi Medical University, Zunyi, China
| | - Cheng-Xi Liu
- Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi, China
| | - Yu Zhang
- Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi, China
| | - Lin Zhang
- Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi, China
| | - Liang Zhou
- Key Laboratory of Brain Science, Zunyi Medical University, Zunyi, China
| | - Tian Yu
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi, China.,Key Laboratory of Brain Science, Zunyi Medical University, Zunyi, China
| | - Shou-Yang Yu
- Key Laboratory of Brain Science, Zunyi Medical University, Zunyi, China
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Tsurugizawa T, Tamada K, Ono N, Karakawa S, Kodama Y, Debacker C, Hata J, Okano H, Kitamura A, Zalesky A, Takumi T. Awake functional MRI detects neural circuit dysfunction in a mouse model of autism. SCIENCE ADVANCES 2020; 6:eaav4520. [PMID: 32076634 PMCID: PMC7002125 DOI: 10.1126/sciadv.aav4520] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 11/22/2019] [Indexed: 05/05/2023]
Abstract
MRI has potential as a translational approach from rodents to humans. However, given that mouse functional MRI (fMRI) uses anesthetics for suppression of motion, it has been difficult to directly compare the result of fMRI in "unconsciousness" disease model mice with that in "consciousness" patients. We develop awake fMRI to investigate brain function in 15q dup mice, a copy number variation model of autism. Compared to wild-type mice, we find that 15q dup is associated with whole-brain functional hypoconnectivity and diminished fMRI responses to odors of stranger mice. Ex vivo diffusion MRI reveals widespread anomalies in white matter ultrastructure in 15q dup mice, suggesting a putative anatomical substrate for these functional hypoconnectivity. We show that d-cycloserine (DCS) treatment partially normalizes these anormalies in the frontal cortex of 15q dup mice and rescues some social behaviors. Our results demonstrate the utility of awake rodent fMRI and provide a rationale for further investigation of DCS therapy.
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Affiliation(s)
- Tomokazu Tsurugizawa
- NeuroSpin, Commissariat à l’Energie Atomique et aux Energies Alternatives, CEA Saclay, Gif-sur-Yvette 91191, France
- Corresponding author. (T.Ts.); (T.Ta.)
| | - Kota Tamada
- RIKEN Brain Science Institute, Wako, Saitama 351-0198, Japan
| | - Nobukazu Ono
- Institute for Innovation, Ajinomoto Co. Inc., Kawasaki 210-8681, Japan
| | - Sachise Karakawa
- Institute for Innovation, Ajinomoto Co. Inc., Kawasaki 210-8681, Japan
| | - Yuko Kodama
- Institute for Innovation, Ajinomoto Co. Inc., Kawasaki 210-8681, Japan
| | - Clement Debacker
- NeuroSpin, Commissariat à l’Energie Atomique et aux Energies Alternatives, CEA Saclay, Gif-sur-Yvette 91191, France
| | - Junichi Hata
- RIKEN Brain Science Institute, Wako, Saitama 351-0198, Japan
- Department of Physiology, Keio University School of Medicine, Shinjuku, Tokyo 160-8585, Japan
| | - Hideyuki Okano
- RIKEN Brain Science Institute, Wako, Saitama 351-0198, Japan
- Department of Physiology, Keio University School of Medicine, Shinjuku, Tokyo 160-8585, Japan
| | - Akihiko Kitamura
- Institute for Innovation, Ajinomoto Co. Inc., Kawasaki 210-8681, Japan
| | - Andrew Zalesky
- Melbourne Neuropsychiatry Centre and Department of Biomedical Engineering, University of Melbourne, Victoria 3010, Australia
| | - Toru Takumi
- RIKEN Brain Science Institute, Wako, Saitama 351-0198, Japan
- Department of Physiology and Cell Biology, Kobe University School of Medicine, Chuo, Kobe 650-0017, Japan
- Corresponding author. (T.Ts.); (T.Ta.)
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11
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Esteves M, Almeida AM, Silva J, Silva Moreira P, Carvalho E, Pêgo JM, Almeida A, Sotiropoulos I, Sousa N, Leite-Almeida H. MORPhA Scale: Behavioral and electroencephalographic validation of a rodent anesthesia scale. J Neurosci Methods 2019; 324:108304. [DOI: 10.1016/j.jneumeth.2019.05.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 05/24/2019] [Accepted: 05/25/2019] [Indexed: 10/26/2022]
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12
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Gao S, Proekt A, Renier N, Calderon DP, Pfaff DW. Activating an anterior nucleus gigantocellularis subpopulation triggers emergence from pharmacologically-induced coma in rodents. Nat Commun 2019; 10:2897. [PMID: 31263107 PMCID: PMC6603023 DOI: 10.1038/s41467-019-10797-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 06/01/2019] [Indexed: 02/08/2023] Open
Abstract
Multiple areas within the reticular activating system (RAS) can hasten awakening from sleep or light planes of anesthesia. However, stimulation in individual sites has shown limited recovery from deep global suppression of brain activity, such as coma. Here we identify a subset of RAS neurons within the anterior portion of nucleus gigantocellularis (aNGC) capable of producing a high degree of awakening represented by a broad high frequency cortical reactivation associated with organized movements and behavioral reactivity to the environment from two different models of deep pharmacologically-induced coma (PIC): isoflurane (1.25%-1.5%) and induced hypoglycemic coma. Activating aNGC neurons triggered awakening by recruiting cholinergic, noradrenergic, and glutamatergic arousal pathways. In summary, we identify an evolutionarily conserved population of RAS neurons, which broadly restore cerebral cortical activation and motor behavior in rodents through the coordinated activation of multiple arousal-promoting circuits.
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Affiliation(s)
- S Gao
- Department of Anesthesiology, Weill Cornell Medical College, New York, NY, 10065, USA
| | - A Proekt
- Department of Anesthesiology, Weill Cornell Medical College, New York, NY, 10065, USA
- Laboratory of Neurobiology and Behavior, the Rockefeller University, New York, NY, 10065, USA
| | - N Renier
- ICM, Brain and Spine Institute, Hopital de la Pitie-Salpetriere, Sorbonne Universite, Inserm, CNRS, Paris, 75013, France
| | - D P Calderon
- Department of Anesthesiology, Weill Cornell Medical College, New York, NY, 10065, USA.
- Laboratory of Neurobiology and Behavior, the Rockefeller University, New York, NY, 10065, USA.
| | - D W Pfaff
- Laboratory of Neurobiology and Behavior, the Rockefeller University, New York, NY, 10065, USA
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13
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Luo T, Yu S, Cai S, Zhang Y, Jiao Y, Yu T, Yu W. Parabrachial Neurons Promote Behavior and Electroencephalographic Arousal From General Anesthesia. Front Mol Neurosci 2018; 11:420. [PMID: 30564094 PMCID: PMC6288364 DOI: 10.3389/fnmol.2018.00420] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Accepted: 10/26/2018] [Indexed: 12/21/2022] Open
Abstract
General anesthesia has been used clinically for more than 170 years, yet its underlying mechanisms are still not fully understood. The parabrachial nucleus (PBN) in the brainstem has been known to be crucial for regulating wakefulness and signs of arousal on the cortical electroencephalogram (EEG). Lesions of the parabrachial complex lead to unresponsiveness and a monotonous high-voltage, and a slow-wave EEG, which are the two main features of general anesthesia. However, it is unclear whether and how the PBN functions in the process of general anesthesia. By recording the levels of calcium in vivo in real-time, we found that the neural activity in PBN is suppressed during anesthesia, while it is robustly activated during recovery from propofol and isoflurane anesthesia. The activation of PBN neurons by “designer receptors exclusively activated by designer drugs” (DREADDs) shortened the recovery time but did not change the induction time. Cortical EEG recordings revealed that the neural activation of PBN specifically affected the recovery period, with a decrease of δ-band power or an increase in β-band power; no EEG changes were seen in the anesthesia period. Furthermore, the activation of PBN elicited neural activation in the prefrontal cortex, basal forebrain, lateral hypothalamus, thalamus, and supramammillary nucleus. Thus, PBN is critical for behavioral and electroencephalographic arousal without affecting the induction of general anesthesia.
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Affiliation(s)
- Tianyuan Luo
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.,Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi Medical College, Zunyi, China
| | - Shouyang Yu
- Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi Medical College, Zunyi, China
| | - Shuang Cai
- Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi Medical College, Zunyi, China
| | - Yu Zhang
- Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi Medical College, Zunyi, China
| | - Yingfu Jiao
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Tian Yu
- Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi Medical College, Zunyi, China
| | - Weifeng Yu
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
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14
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Lee DE, Lee LG, Siu D, Bazrafkan AK, Farahabadi MH, Dinh TJ, Orellana J, Xiong W, Lopour BA, Akbari Y. Neural Correlates of Consciousness at Near-Electrocerebral Silence in an Asphyxial Cardiac Arrest Model. Brain Connect 2017; 7:172-181. [PMID: 28398813 PMCID: PMC5399737 DOI: 10.1089/brain.2016.0471] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
Recent electrophysiological studies have suggested surges in electrical correlates of consciousness (i.e., elevated gamma power and connectivity) after cardiac arrest (CA). This study examines electrocorticogram (ECoG) activity and coherence of the dying brain during asphyxial CA. Male Wistar rats (n = 16) were induced with isoflurane anesthesia, which was washed out before asphyxial CA. Mean phase coherence and ECoG power were compared during different stages of the asphyxial period to assess potential neural correlates of consciousness. After asphyxia, the ECoG progressed through four distinct stages (asphyxial stages 1-4 [AS1-4]), including a transient period of near-electrocerebral silence lasting several seconds (AS3). Electrocerebral silence (AS4) occurred within 1 min of the start of asphyxia, and pulseless electrical activity followed the start of AS4 by 1-2 min. AS3 was linked to a significant increase in frontal coherence between the left and right motor cortices (p < 0.05), with no corresponding increase in ECoG power. AS3 was also associated with a significant posterior shift of ECoG power, favoring the visual cortices (p < 0.05). Although the ECoG during AS3 appears visually flat or silent when viewed with standard clinical settings, our study suggests that this period of transient near-electrocerebral silence contains distinctive neural activity. Specifically, the burst in frontal coherence and posterior shift of ECoG power that we find during this period immediately preceding CA may be a neural correlate of conscious processing.
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Affiliation(s)
- Donald E. Lee
- Department of Neurology, University of California, Irvine, California
| | - Lauren G. Lee
- Department of Neurology, University of California, Irvine, California
| | - Danny Siu
- Department of Neurology, University of California, Irvine, California
| | | | | | - Tin J. Dinh
- Department of Neurology, University of California, Irvine, California
| | - Josue Orellana
- Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, Pennsylvania
| | - Wei Xiong
- Department of Neurology, Case Western Reserve University School of Medicine, Cleveland, Ohio
| | - Beth A. Lopour
- Department of Biomedical Engineering, University of California, Irvine, California
| | - Yama Akbari
- Department of Neurology, University of California, Irvine, California
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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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16
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Kortelainen J, Al-Nashash H, Vipin A, Thow XY, All A. The effect of anaesthesia on somatosensory evoked potential measurement in a rat model. Lab Anim 2015; 50:63-6. [DOI: 10.1177/0023677215589514] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Somatosensory evoked potentials (SEPs) are widely used to study the functional integrity of ascending sensory pathways. For animal studies, SEPs provide a convenient method to quantitatively assess the functionality of the nervous system with low invasiveness. Even though they are frequently used in animal models, little attention is paid to the fact that SEPs are vulnerable to contamination from experimental factors such as anaesthetic delivery. In this study, the effect of isoflurane on SEP measurement was investigated in a rat model. The aim was to find out the adjustments for anaesthetic delivery optimizing the quality of the recordings. Two aspects were studied: the effect of isoflurane dosage on the SEP parameters and on the repeatability of the measurements. The SEP quality was found to be best when 1.5% isoflurane concentration was used. This dosage resulted in the best signal-to-noise ratio and equal repeatability of the measurements compared with the others. Our findings can help in refining the anaesthetic protocols related to SEP recordings in a rat model and, by improving the quality of the measurements, potentially reducing the number of subjects needed to carry out studies.
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Affiliation(s)
- Jukka Kortelainen
- Biomedical Engineering Research Group, Department of Computer Science and Engineering, University of Oulu, Oulu, Finland
- Singapore Institute for Neurotechnology (SINAPSE), National University of Singapore, Singapore
| | - Hasan Al-Nashash
- Singapore Institute for Neurotechnology (SINAPSE), National University of Singapore, Singapore
- Department of Electrical Engineering, American University of Sharjah, Sharjah, United Arab Emirates
| | - Ashwati Vipin
- Singapore Institute for Neurotechnology (SINAPSE), National University of Singapore, Singapore
| | - Xin Yuan Thow
- Singapore Institute for Neurotechnology (SINAPSE), National University of Singapore, Singapore
| | - Angelo All
- Department of Orthopedic Surgery and Biomedical Engineering, National University of Singapore, Singapore
- Department of Neurology and Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
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17
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Attenuation of high-frequency (50-200 Hz) thalamocortical EEG rhythms by propofol in rats is more pronounced for the thalamus than for the cortex. PLoS One 2015; 10:e0123287. [PMID: 25875024 PMCID: PMC4398544 DOI: 10.1371/journal.pone.0123287] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 02/09/2015] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Thalamocortical EEG rhythms in gamma (30-80 Hz) and high-gamma (80-200 Hz) ranges have been linked to arousal and conscious processes. To test the hypothesis that general anesthetics attenuate these rhythms, we characterized the concentration-effect relationship of propofol on the spectral power of these rhythms. In view of the ongoing debate about cortex versus thalamus as the primary site of anesthetic action for unconsciousness, we also compared the relative sensitivity of cortex and thalamus to this effect propofol. METHODS Adult male Long-Evans rats were chronically implanted with electrodes in somatosensory (barrel) cortex and ventroposteromedial thalamus. Propofol was delivered by a computer-controlled infusion using real-time pharmacokinetic modeling to obtain the desired plasma concentration. Spectral power was assessed during baseline, at four stable propofol plasma-concentrations (0, 3,6,9,12 μg/ml) and during recovery over four frequency ranges (30-50, 51-75, 76-125, 126-200 Hz). Unconsciousness was defined as complete loss of righting reflex. Multiple regression was used to model the change of power (after logarithmic transformation) as a function of propofol concentration and recording site. RESULTS Unconsciousness occurred at the 9 μg/ml concentration in all animals. Propofol caused a robust linear concentration-dependent attenuation of cortical power in the 76-200 Hz range and of thalamic power in the 30-200 Hz range. In all instances the concentration-effect slope for the thalamus was markedly steeper than for the cortex. Furthermore the lowest concentration causing unconsciousness significantly reduced cortical power in the 126-200 Hz range and thalamic power in the 30-200 Hz range. CONCLUSIONS Propofol causes a concentration-dependent attenuation of the power of thalamocortical rhythms in the 30-200 Hz range and this effect is far more pronounced for the thalamus, where the attenuation provides a robust correlate of the hypnotic action of propofol [corrected].
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18
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Induction of self awareness in dreams through frontal low current stimulation of gamma activity. Nat Neurosci 2014; 17:810-2. [DOI: 10.1038/nn.3719] [Citation(s) in RCA: 226] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 04/16/2014] [Indexed: 11/08/2022]
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Kortelainen J, Vipin A, Mir H, Thakor N, Al-Nashash H, All A. Effect of isoflurane on somatosensory evoked potentials in a rat model. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2014; 2014:4286-4289. [PMID: 25570940 DOI: 10.1109/embc.2014.6944572] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Somatosensory evoked potentials (SEPs) are widely used in the clinic as well as research to study the functional integrity of the different parts of sensory pathways. However, most general anesthetics, such as isoflurane, are known to suppress SEPs, which might affect the interpretation of the signals. In animal studies, the usage of anesthetics during SEP measurements is inevitable due to which detailed effect of these drugs on the recordings should be known. In this paper, the effect of isoflurane on SEPs was studied in a rat model. Both time and frequency properties of the cortical recordings generated by stimulating the tibial nerve of rat's hindlimb were investigated at three different isoflurane levels. While the anesthetic agent is shown to generally suppress the amplitude of the SEP, the effect was found to be nonlinear influencing more substantially the latter part of waveform. This finding will potentially help us in future work aiming at separating the effects of anesthetics on SEP from those due to injury in the ascending neural pathways.
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20
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Sury MRJ, Worley A, Boyd SG. Age-related changes in EEG power spectra in infants during sevoflurane wash-out. Br J Anaesth 2013; 112:686-94. [PMID: 24346023 DOI: 10.1093/bja/aet409] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Few electroencephalography (EEG) data are available in anaesthetized infants. This study aimed to identify EEG characteristics that might warn of awakening (AW) from sevoflurane anaesthesia in infants. METHODS Twenty intubated infants [aged 39-77 weeks post-menstrual age (PMA)] were studied after surgery during sevoflurane wash-out. EEG was recorded at the end of surgery and throughout emergence. Changes in EEG time and frequency domains were described. RESULTS At the end of surgery, mean end-tidal sevoflurane concentration was 2.3% (range 1.5-3.5) before wash-out and reduced to 0.3% (0.1-0.6) when AW began. On AW, movement artifacts made signals difficult to interpret. Before awakening, most power was within frequencies ≤4 Hz, but trends over time were variable. Summated power in frequencies between 20 and 70 Hz was almost always <5 µV(2). During anaesthesia, there were two common power spectra: infants >52 weeks PMA had obvious summated power in the frequency range 5-20 Hz (P5-20 Hz) (mean 308, median 320, range 110-542 µV(2)), which decreased before awakening began [mean decrease 252 µV(2) (95% CI 153-351)], whereas younger infants had low P5-20 Hz throughout. P5-20 Hz during anaesthesia increased with age; power in this frequency band of ~100 µV(2) separated infants younger and older than 52 weeks PMA. CONCLUSIONS During sevoflurane wash-out, decreasing P5-20 Hz might warn of impending AW in infants >3 months old, but not in younger infants.
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Affiliation(s)
- M R J Sury
- Department of Anaesthesia, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
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21
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Sanoja R, Taepavarapruk N, Benda E, Tadavarty R, Soja PJ. Enhanced excitability of thalamic sensory neurons and slow-wave EEG pattern after stimuli that induce spinal long-term potentiation. J Neurosci 2013; 33:15109-19. [PMID: 24048841 PMCID: PMC6618413 DOI: 10.1523/jneurosci.2110-13.2013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Revised: 07/24/2013] [Accepted: 08/13/2013] [Indexed: 11/21/2022] Open
Abstract
Spinal nociceptive neurons are well known to undergo a process of long-term potentiation (LTP) following conditioning by high-frequency sciatic nerve stimulation (HFS) at intensities recruiting C-fibers. However, little if any information exists as to whether such HFS conditioning that produces spinal LTP affects sensory transmission at supraspinal levels. The present study explored this possibility. Conventional extracellular recording methods were used to examine the consequences of HFS versus sham HFS conditioning on individual wide-dynamic range thalamic neurons located in the ventro-postero-lateral (VPL) nucleus in isoflurane-anesthetized rats. Following HFS, the ongoing firing rate and stimulus-evoked (brush, pinch, sciatic nerve) responses were markedly enhanced as were responses to juxtacellular, microiontophoretic applications of glutamate. These HFS-induced enhancements lasted throughout the recording period. Sham stimuli had no effect on VPL neuron excitability. Cortical electroencephalographic (EEG) wave activities were also measured around HFS in conjunction with VPL neuron recordings. The cortical EEG pattern under baseline conditions consisted of recurring short duration bursts of high-amplitude slow waves followed by longer periods of flat EEG. Following HFS, the EEG shifted to a continuous large-amplitude, slow-wave pattern within the 0.5-8.0 Hz bandwidth lasting throughout the recording period. Sham HFS did not alter EEG activity. Sciatic nerve conditioning at A-δ fiber strength, known to reverse spinal LTP, did not alter enhanced neuronal excitability or the EEG slow-wave pattern induced by HFS. These data support the concept that HFS conditioning of the sciatic nerve, which leads to spinal LTP, is associated with distinct, long-lasting changes in the excitability of neurons comprising thalamocortical networks.
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Affiliation(s)
- Raul Sanoja
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia, V6T 1Z3 Canada
| | - Niwat Taepavarapruk
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia, V6T 1Z3 Canada
| | - Elke Benda
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia, V6T 1Z3 Canada
| | - Ramakrishna Tadavarty
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia, V6T 1Z3 Canada
| | - Peter J. Soja
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia, V6T 1Z3 Canada
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Kortelainen J, Väyrynen E, Jia X, Seppänen T, Thakor N. EEG-based detection of awakening from isoflurane anesthesia in rats. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2013; 2012:4279-82. [PMID: 23366873 DOI: 10.1109/embc.2012.6346912] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In animal studies, reliable measures for depth of anesthesia are frequently required. Previous findings suggest that the continuous depth of anesthesia indices developed for humans might not be adequate for rats whose EEG changes during anesthesia represent more of quick transitions between discrete states. In this paper, the automatic EEG-based detection of awakening from anesthesia was studied in rats. An algorithm based on Bayesian Information Criterion (BIC) is proposed for the assessment of the switch-like change in the signal characteristics occurring just before the awakening. The method was tested with EEGs recorded from ten rats recovering from isoflurane anesthesia. The algorithm was shown to be able to detect the sudden change in the EEG related to the moment of awakening with a precision comparable to careful visual inspection. Our findings suggest that monitoring such signal changes may offer an interesting alternative to the application of continuous depth of anesthesia indices when avoiding the awakening of the animal during e.g. a clinical experiment.
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Affiliation(s)
- Jukka Kortelainen
- Department of Computer Science and Engineering, BOX 4500, FIN-90014 University of Oulu, Finland.
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23
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Boudewijns ZSRM, Groen MR, Lodder B, McMaster MTB, Kalogreades L, de Haan R, Narayanan RT, Meredith RM, Mansvelder HD, de Kock CPJ. Layer-specific high-frequency action potential spiking in the prefrontal cortex of awake rats. Front Cell Neurosci 2013; 7:99. [PMID: 23805075 PMCID: PMC3693071 DOI: 10.3389/fncel.2013.00099] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Accepted: 06/06/2013] [Indexed: 11/20/2022] Open
Abstract
Cortical pyramidal neurons show irregular in vivo action potential (AP) spiking with high-frequency bursts occurring on sparse background activity. Somatic APs can backpropagate from soma into basal and apical dendrites and locally generate dendritic calcium spikes. The critical AP frequency for generation of such dendritic calcium spikes can be very different depending on cell type or brain area involved. Previously, it was shown in vitro that calcium electrogenesis can be induced in L(ayer) 5 pyramidal neurons of prefrontal cortex (PFC). It remains an open question whether somatic burst spiking and the resulting dendritic calcium electrogenesis also occur in morphologically more compact L2/3 pyramidal neurons. Furthermore, it is not known whether critical frequencies that trigger dendritic calcium electrogenesis occur in PFC under awake conditions in vivo. Here, we addressed these issues and found that pyramidal neurons in both PFC L2/3 and L5 in awake rats spike APs in short bursts but with different probabilities. The critical frequency (CF) for calcium electrogenesis in vitro was layer-specific and lower in L5 neurons compared to L2/3. Taking the in vitro CF as a predictive measure for dendritic electrogenesis during in vivo spontaneous activity, supracritical bursts in vivo were observed in a larger fraction of L5 neurons compared to L2/3 neurons but with similar incidence within these subpopulations. Together, these results show that in PFC of awake rats, AP spiking occurs at frequencies that are relevant for dendritic calcium electrogenesis and suggest that in awake rat PFC, dendritic calcium electrogenesis may be involved in neuronal computation.
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Affiliation(s)
- Zimbo S R M Boudewijns
- Department of Integrative Neurophysiology, Centre for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, Vrije Universiteit Amsterdam Amsterdam, Netherlands
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