1
|
Aggarwal A, Luo J, Chung H, Contreras D, Kelz MB, Proekt A. Neural assemblies coordinated by cortical waves are associated with waking and hallucinatory brain states. Cell Rep 2024; 43:114017. [PMID: 38578827 DOI: 10.1016/j.celrep.2024.114017] [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: 07/11/2023] [Revised: 01/08/2024] [Accepted: 03/14/2024] [Indexed: 04/07/2024] Open
Abstract
The relationship between sensory stimuli and perceptions is brain-state dependent: in wakefulness, suprathreshold stimuli evoke perceptions; under anesthesia, perceptions are abolished; and during dreaming and in dissociated states, percepts are internally generated. Here, we exploit this state dependence to identify brain activity associated with internally generated or stimulus-evoked perceptions. In awake mice, visual stimuli phase reset spontaneous cortical waves to elicit 3-6 Hz feedback traveling waves. These stimulus-evoked waves traverse the cortex and entrain visual and parietal neurons. Under anesthesia as well as during ketamine-induced dissociation, visual stimuli do not disrupt spontaneous waves. Uniquely, in the dissociated state, spontaneous waves traverse the cortex caudally and entrain visual and parietal neurons, akin to stimulus-evoked waves in wakefulness. Thus, coordinated neuronal assemblies orchestrated by traveling cortical waves emerge in states in which perception can manifest. The awake state is privileged in that this coordination is reliably elicited by external visual stimuli.
Collapse
Affiliation(s)
- Adeeti Aggarwal
- Department of Ophthalmology, Stanford University, Palo Alto, CA 94303, USA; Department of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jennifer Luo
- School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Helen Chung
- The College of Arts & Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Diego Contreras
- Department of Ophthalmology, Stanford University, Palo Alto, CA 94303, USA; Mahoney Institute for Neuroscience, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Max B Kelz
- Department of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Mahoney Institute for Neuroscience, University of Pennsylvania, Philadelphia, PA 19104, USA; Center for the Neuroscience of Unconsciousness and Reanimation Research Alliance (NEURRAL), University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Alex Proekt
- Department of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Mahoney Institute for Neuroscience, University of Pennsylvania, Philadelphia, PA 19104, USA; Center for the Neuroscience of Unconsciousness and Reanimation Research Alliance (NEURRAL), University of Pennsylvania, Philadelphia, PA 19104, USA.
| |
Collapse
|
2
|
Wasilczuk AZ, Rinehart C, Aggarwal A, Stone ME, Mashour GA, Avidan MS, Kelz MB, Proekt A. Hormonal basis of sex differences in anesthetic sensitivity. Proc Natl Acad Sci U S A 2024; 121:e2312913120. [PMID: 38190526 PMCID: PMC10801881 DOI: 10.1073/pnas.2312913120] [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: 07/27/2023] [Accepted: 11/20/2023] [Indexed: 01/10/2024] Open
Abstract
General anesthesia-a pharmacologically induced reversible state of unconsciousness-enables millions of life-saving procedures. Anesthetics induce unconsciousness in part by impinging upon sexually dimorphic and hormonally sensitive hypothalamic circuits regulating sleep and wakefulness. Thus, we hypothesized that anesthetic sensitivity should be sex-dependent and modulated by sex hormones. Using distinct behavioral measures, we show that at identical brain anesthetic concentrations, female mice are more resistant to volatile anesthetics than males. Anesthetic sensitivity is bidirectionally modulated by testosterone. Castration increases anesthetic resistance. Conversely, testosterone administration acutely increases anesthetic sensitivity. Conversion of testosterone to estradiol by aromatase is partially responsible for this effect. In contrast, oophorectomy has no effect. To identify the neuronal circuits underlying sex differences, we performed whole brain c-Fos activity mapping under anesthesia in male and female mice. Consistent with a key role of the hypothalamus, we found fewer active neurons in the ventral hypothalamic sleep-promoting regions in females than in males. In humans, we demonstrate that females regain consciousness and recover cognition faster than males after identical anesthetic exposures. Remarkably, while behavioral and neurocognitive measures in mice and humans point to increased anesthetic resistance in females, cortical activity fails to show sex differences under anesthesia in either species. Cumulatively, we demonstrate that sex differences in anesthetic sensitivity are evolutionarily conserved and not reflected in conventional electroencephalographic-based measures of anesthetic depth. This covert resistance to anesthesia may explain the higher incidence of unintended awareness under general anesthesia in females.
Collapse
Affiliation(s)
- Andrzej Z. Wasilczuk
- Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, PA19104
- Neuroscience of Unconsciousness and Reanimation Research Alliance, Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, PA19104
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA19104
| | - Cole Rinehart
- Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, PA19104
- Neuroscience of Unconsciousness and Reanimation Research Alliance, Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, PA19104
| | - Adeeti Aggarwal
- Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, PA19104
- Neuroscience of Unconsciousness and Reanimation Research Alliance, Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, PA19104
- Department of Neuroscience, University of Pennsylvania, Philadelphia, PA19104
| | - Martha E. Stone
- Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, PA19104
- Neuroscience of Unconsciousness and Reanimation Research Alliance, Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, PA19104
- Department of Neuroscience, University of Pennsylvania, Philadelphia, PA19104
| | - George A. Mashour
- Center for Consciousness Science, Department of Anesthesiology, University of Michigan Medical School, Ann Arbor, MI48105
| | - Michael S. Avidan
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO63110
| | - Max B. Kelz
- Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, PA19104
- Neuroscience of Unconsciousness and Reanimation Research Alliance, Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, PA19104
- Department of Neuroscience, University of Pennsylvania, Philadelphia, PA19104
- Mahoney Institute for Neurosciences, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA19104
| | - Alex Proekt
- Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, PA19104
- Neuroscience of Unconsciousness and Reanimation Research Alliance, Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, PA19104
- Department of Neuroscience, University of Pennsylvania, Philadelphia, PA19104
- Mahoney Institute for Neurosciences, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA19104
| | - ReCCognition Study Group
- Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, PA19104
- Center for Consciousness Science, Department of Anesthesiology, University of Michigan Medical School, Ann Arbor, MI48105
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO63110
| |
Collapse
|
3
|
Ma H, Gu L, Wang Y, Xu Q, Zhang Y, Shao W, Yu Q, Lian X, Liu L, Gu J, Ji N, Liu X, Nagayasu K, Zhang H. The States of Different 5-HT Receptors Located in the Dorsal Raphe Nucleus Are Crucial for Regulating the Awakening During General Anesthesia. Mol Neurobiol 2023; 60:6931-6948. [PMID: 37516665 DOI: 10.1007/s12035-023-03519-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 07/11/2023] [Indexed: 07/31/2023]
Abstract
General anesthesia is widely used in various clinical practices due to its ability to cause loss of consciousness. However, the exact mechanism of anesthesia-induced unconsciousness remains unclear. It is generally thought that arousal-related brain nuclei are involved. 5-Hydroxytryptamine (5-HT) is closely associated with sleep arousal. Here, we explore the role of the 5-HT system in anesthetic awakening through pharmacological interventions and optogenetic techniques. Our data showed that exogenous administration of 5-hydroxytryptophan (5-HTP) and optogenetic activation of 5-HT neurons in the dorsal raphe nucleus (DR) could significantly shorten the emergence time of sevoflurane anesthesia in mice, suggesting that regulation of the 5-HT system using both endogenous and exogenous approaches could mediate delayed emergence. In addition, we first discovered that the different 5-HT receptors located in the DR, known as 5-HT autoreceptors, are essential for the regulation of general anesthetic awakening, with 5-HT1A and 5-HT2A/C receptors playing a regulatory role. These results can provide a reliable theoretical basis as well as potential targets for clinical intervention to prevent delayed emergence and some postoperative risks.
Collapse
Affiliation(s)
- HaiXiang Ma
- Department of Anesthesiology, The Fourth School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, 310006, China
- Medical College of Jining Medical University, Ningji, 272067, Shandong, China
| | - LeYuan Gu
- Department of Anesthesiology, The Fourth School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, 310006, China
| | - YuLing Wang
- Department of Anesthesiology, The Fourth School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, 310006, China
| | - Qing Xu
- Department of Anesthesiology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, China
| | - Yuanli Zhang
- Department of Anesthesiology, The Fourth School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, 310006, China
| | - WeiHui Shao
- Department of Anesthesiology, The Fourth School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, 310006, China
| | - Qian Yu
- Department of Anesthesiology, The Fourth School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, 310006, China
| | - XiTing Lian
- Department of Anesthesiology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, China
| | - Lu Liu
- Department of Anesthesiology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, China
| | - JiaXuan Gu
- Department of Anesthesiology, The Fourth School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, 310006, China
| | - Na Ji
- Department of Anesthesia, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, China
| | - XiaoLing Liu
- Department of Anesthesiology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, China
| | - Kazuki Nagayasu
- Department of Molecular Pharmacology, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, 606-8501, Japan
| | - HongHai Zhang
- Department of Anesthesiology, The Fourth School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, 310006, China.
- Medical College of Jining Medical University, Ningji, 272067, Shandong, China.
- Department of Anesthesiology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, China.
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, 310006, China.
| |
Collapse
|
4
|
Dai W, Wang T, Li Y, Yang Y, Zhang Y, Kang J, Wu Y, Yu H, Xing D. Dynamic Recruitment of the Feedforward and Recurrent Mechanism for Black-White Asymmetry in the Primary Visual Cortex. J Neurosci 2023; 43:5668-5684. [PMID: 37487737 PMCID: PMC10401654 DOI: 10.1523/jneurosci.0168-23.2023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 07/11/2023] [Accepted: 07/14/2023] [Indexed: 07/26/2023] Open
Abstract
Black and white information is asymmetrically distributed in natural scenes, evokes asymmetric neuronal responses, and causes asymmetric perceptions. Recognizing the universality and essentiality of black-white asymmetry in visual information processing, the neural substrates for black-white asymmetry remain unclear. To disentangle the role of the feedforward and recurrent mechanisms in the generation of cortical black-white asymmetry, we recorded the V1 laminar responses and LGN responses of anesthetized cats of both sexes. In a cortical column, we found that black-white asymmetry starts at the input layer and becomes more pronounced in the output layer. We also found distinct dynamics of black-white asymmetry between the output layer and the input layer. Specifically, black responses dominate in all layers after stimulus onset. After stimulus offset, black and white responses are balanced in the input layer, but black responses still dominate in the output layer. Compared with that in the input layer, the rebound response in the output layer is significantly suppressed. The relative suppression strength evoked by white stimuli is notably stronger and depends on the location within the ON-OFF cortical map. A model with delayed and polarity-selective cortical suppression explains black-white asymmetry in the output layer, within which prominent recurrent connections are identified by Granger causality analysis. In addition to black-white asymmetry in response strength, the interlaminar differences in spatial receptive field varied dynamically. Our findings suggest that the feedforward and recurrent mechanisms are dynamically recruited for the generation of black-white asymmetry in V1.SIGNIFICANCE STATEMENT Black-white asymmetry is universal and essential in visual information processing, yet the neural substrates for cortical black-white asymmetry remain unknown. Leveraging V1 laminar recordings, we provided the first laminar pattern of black-white asymmetry in cat V1 and found distinct dynamics of black-white asymmetry between the output layer and the input layer. Comparing black-white asymmetry across three visual hierarchies, the LGN, V1 input layer, and V1 output layer, we demonstrated that the feedforward and recurrent mechanisms are dynamically recruited for the generation of cortical black-white asymmetry. Our findings not only enhance our understanding of laminar processing within a cortical column but also elucidate how feedforward connections and recurrent connections interact to shape neuronal response properties.
Collapse
Affiliation(s)
- Weifeng Dai
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China
| | - Tian Wang
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China
- College of Life Sciences, Beijing Normal University, Beijing, 100875, China
| | - Yang Li
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China
| | - Yi Yang
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China
| | - Yange Zhang
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China
| | - Jian Kang
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China
| | - Yujie Wu
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China
| | - Hongbo Yu
- School of Life Sciences, State Key Laboratory of Medical Neurobiology, Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200438, China
| | - Dajun Xing
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, 100875, China
| |
Collapse
|
5
|
Aggarwal A, Luo J, Chung H, Contreras D, Kelz MB, Proekt A. Neural assemblies coordinated by cortical waves are associated with waking and hallucinatory brain states. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.22.540656. [PMID: 37292587 PMCID: PMC10245750 DOI: 10.1101/2023.05.22.540656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The relationship between sensory stimuli and perceptions is brain-state dependent: in wakefulness stimuli evoke perceptions; under anesthesia perceptions are abolished; during dreaming and in dissociated states, percepts are internally generated. Here, we exploit this state dependence to identify brain activity associated with internally generated or stimulus-evoked perception. In awake mice, visual stimuli phase reset spontaneous cortical waves to elicit 3-6 Hz feedback traveling waves. These stimulus-evoked waves traverse the cortex and entrain visual and parietal neurons. Under anesthesia and during ketamine-induced dissociation, visual stimuli do not disrupt spontaneous waves. Uniquely in the dissociated state, spontaneous waves traverse the cortex caudally and entrain visual and parietal neurons, akin to stimulus-evoked waves in wakefulness. Thus, coordinated neuronal assemblies orchestrated by traveling cortical waves emerge in states in which perception can manifest. The awake state is privileged in that this coordination is elicited by specifically by external visual stimuli.
Collapse
|
6
|
Visual evoked feedforward-feedback traveling waves organize neural activity across the cortical hierarchy in mice. Nat Commun 2022; 13:4754. [PMID: 35963850 PMCID: PMC9376099 DOI: 10.1038/s41467-022-32378-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 07/27/2022] [Indexed: 12/26/2022] Open
Abstract
Sensory processing is distributed among many brain regions that interact via feedforward and feedback signaling. Neuronal oscillations have been shown to mediate intercortical feedforward and feedback interactions. Yet, the macroscopic structure of the multitude of such oscillations remains unclear. Here, we show that simple visual stimuli reliably evoke two traveling waves with spatial wavelengths that cover much of the cerebral hemisphere in awake mice. 30-50 Hz feedforward waves arise in primary visual cortex (V1) and propagate rostrally, while 3-6 Hz feedback waves originate in the association cortex and flow caudally. The phase of the feedback wave modulates the amplitude of the feedforward wave and synchronizes firing between V1 and parietal cortex. Altogether, these results provide direct experimental evidence that visual evoked traveling waves percolate through the cerebral cortex and coordinate neuronal activity across broadly distributed networks mediating visual processing.
Collapse
|
7
|
Dvořáková L, Stenroos P, Paasonen E, Salo RA, Paasonen J, Gröhn O. Light sedation with short habituation time for large-scale functional magnetic resonance imaging studies in rats. NMR IN BIOMEDICINE 2022; 35:e4679. [PMID: 34961988 PMCID: PMC9285600 DOI: 10.1002/nbm.4679] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 12/14/2021] [Accepted: 12/15/2021] [Indexed: 06/14/2023]
Abstract
Traditionally, preclinical resting state functional magnetic resonance imaging (fMRI) studies have been performed in anesthetized animals. Nevertheless, as anesthesia affects the functional connectivity (FC) in the brain, there has been a growing interest in imaging in the awake state. Obviously, awake imaging requires resource- and time-consuming habituation prior to data acquisition to reduce the stress and motion of the animals. Light sedation has been a less widely exploited alternative for awake imaging, requiring shorter habituation times, while still reducing the effect of anesthesia. Here, we imaged 102 rats under light sedation and 10 awake animals to conduct an FC analysis. We established an automated data-processing pipeline suitable for both groups. Additionally, the same pipeline was used on data obtained from an openly available awake rat database (289 measurements in 90 rats). The FC pattern in the light sedation measurements closely resembled the corresponding patterns in both onsite and offsite awake datasets. However, fewer datasets had to be excluded due to movement in rats with light sedation. The temporal analysis of FC in the lightly sedated group indicated a lingering effect of anesthesia that stabilized after the first 5 min. In summary, our results indicate that the light sedation protocol is a valid alternative for large-scale studies where awake protocols may become prohibitively resource-demanding, as it provides similar results to awake imaging, preserves more scans, and requires shorter habituation times. The large amount of fMRI data obtained in this work are openly available for further analyses.
Collapse
Affiliation(s)
- Lenka Dvořáková
- A. I. V. Institute for Molecular SciencesUniversity of Eastern FinlandKuopioFinland
| | - Petteri Stenroos
- A. I. V. Institute for Molecular SciencesUniversity of Eastern FinlandKuopioFinland
- Grenoble Institut des NeurosciencesUniversité Grenoble AlpesGrenobleFrance
| | - Ekaterina Paasonen
- A. I. V. Institute for Molecular SciencesUniversity of Eastern FinlandKuopioFinland
| | - Raimo A. Salo
- A. I. V. Institute for Molecular SciencesUniversity of Eastern FinlandKuopioFinland
| | - Jaakko Paasonen
- A. I. V. Institute for Molecular SciencesUniversity of Eastern FinlandKuopioFinland
| | - Olli Gröhn
- A. I. V. Institute for Molecular SciencesUniversity of Eastern FinlandKuopioFinland
| |
Collapse
|
8
|
Ward-Flanagan R, Lo AS, Clement EA, Dickson CT. A Comparison of Brain-State Dynamics across Common Anesthetic Agents in Male Sprague-Dawley Rats. Int J Mol Sci 2022; 23:ijms23073608. [PMID: 35408973 PMCID: PMC8998244 DOI: 10.3390/ijms23073608] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/11/2022] [Accepted: 03/21/2022] [Indexed: 02/04/2023] Open
Abstract
Anesthesia is a powerful tool in neuroscientific research, especially in sleep research where it has the experimental advantage of allowing surgical interventions that are ethically problematic in natural sleep. Yet, while it is well documented that different anesthetic agents produce a variety of brain states, and consequently have differential effects on a multitude of neurophysiological factors, these outcomes vary based on dosages, the animal species used, and the pharmacological mechanisms specific to each anesthetic agent. Thus, our aim was to conduct a controlled comparison of spontaneous electrophysiological dynamics at a surgical plane of anesthesia under six common research anesthetics using a ubiquitous animal model, the Sprague-Dawley rat. From this direct comparison, we also evaluated which anesthetic agents may serve as pharmacological proxies for the electrophysiological features and dynamics of unconscious states such as sleep and coma. We found that at a surgical plane, pentobarbital, isoflurane and propofol all produced a continuous pattern of burst-suppression activity, which is a neurophysiological state characteristically observed during coma. In contrast, ketamine-xylazine produced synchronized, slow-oscillatory activity, similar to that observed during slow-wave sleep. Notably, both urethane and chloral hydrate produced the spontaneous, cyclical alternations between forebrain activation (REM-like) and deactivation (non-REM-like) that are similar to those observed during natural sleep. Thus, choice of anesthesia, in conjunction with continuous brain state monitoring, are critical considerations in order to avoid brain-state confounds when conducting neurophysiological experiments.
Collapse
Affiliation(s)
- Rachel Ward-Flanagan
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB T6G 2E1, Canada; (R.W.-F.); (E.A.C.)
| | - Alto S. Lo
- Department of Psychology, University of Alberta, Edmonton, AB T6G 2R3, Canada;
| | - Elizabeth A. Clement
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB T6G 2E1, Canada; (R.W.-F.); (E.A.C.)
| | - Clayton T. Dickson
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB T6G 2E1, Canada; (R.W.-F.); (E.A.C.)
- Department of Psychology, University of Alberta, Edmonton, AB T6G 2R3, Canada;
- Department of Physiology, University of Alberta, Edmonton, AB T6G 2H7, Canada
- Department of Anesthesiology and Pain Medicine, University of Alberta, Edmonton, AB T6G 2G3, Canada
- Correspondence: ; Tel.: +1-(780)-492-7860
| |
Collapse
|
9
|
Castoldi V, d'Isa R, Marenna S, Comi G, Leocani L. Non-invasive visual evoked potentials under sevoflurane versus ketamine-xylazine in rats. Heliyon 2021; 7:e08360. [PMID: 34816047 PMCID: PMC8591496 DOI: 10.1016/j.heliyon.2021.e08360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 03/19/2021] [Accepted: 11/05/2021] [Indexed: 11/17/2022] Open
Abstract
Background Visual Evoked Potential (VEP) quantifies electrical signals produced in visual cortex in response to visual stimuli. VEP elicited by light flashes is a useful biomarker to evaluate visual function in preclinical models and it can be recorded in awake or anaesthetised state. Different types of anaesthesia influence VEP properties, such as latency, which measures the propagation speed along nerve fibers, and amplitude that quantifies the power of electrical signal. Aim The goal of this work is to compare VEPs elicited in Dark Agouti rats under two types of anaesthesia: volatile sevoflurane or injectable ketamine-xylazine. Methods VEP latency, amplitude, signal-to-noise ratio and recording duration were measured in Dark Agouti rats randomly assigned to two groups, the first subjected to volatile sevoflurane and the second to injectable ketamine-xylazine. Taking advantage of non-invasive flash-VEP recording through epidermal cup electrodes, three time points of VEP recordings were assessed in two weeks intervals. Results VEP recorded under ketamine-xylazine showed longer latency and higher amplitude compared with sevoflurane, with analogous repeatability over time. However, sevoflurane tended to suppress electrical signals from visual cortex, resulting in a lower signal-to-noise ratio. Moreover, VEP procedure duration lasted longer in rats anaesthetised with sevoflurane than ketamine-xylazine. Conclusions In Dark Agouti rats, the use of different anaesthesia can influence VEP components in terms of latency and amplitude. Notably, sevoflurane and ketamine-xylazine revealed satisfying repeatability over time, which is critical to perform reliable follow-up studies. Ketamine-xylazine allowed to obtain more clearly discernible VEP components and less background noise, together with a quicker recording procedure and a consequently improved animal safety and welfare.
Collapse
Affiliation(s)
- Valerio Castoldi
- Experimental Neurophysiology Unit, INSPE - Institute of Experimental Neurology, San Raffaele Scientific Institute, Milan, Italy.,Vita-Salute San Raffaele University, Milan, Italy
| | - Raffaele d'Isa
- Experimental Neurophysiology Unit, INSPE - Institute of Experimental Neurology, San Raffaele Scientific Institute, Milan, Italy
| | - Silvia Marenna
- Experimental Neurophysiology Unit, INSPE - Institute of Experimental Neurology, San Raffaele Scientific Institute, Milan, Italy
| | - Giancarlo Comi
- Vita-Salute San Raffaele University, Milan, Italy.,Casa di Cura del Policlinico, Milan, Italy
| | - Letizia Leocani
- Experimental Neurophysiology Unit, INSPE - Institute of Experimental Neurology, San Raffaele Scientific Institute, Milan, Italy.,Vita-Salute San Raffaele University, Milan, Italy
| |
Collapse
|
10
|
Liu D, Li J, Wu J, Dai J, Chen X, Huang Y, Zhang S, Tian B, Mei W. Monochromatic Blue Light Activates Suprachiasmatic Nucleus Neuronal Activity and Promotes Arousal in Mice Under Sevoflurane Anesthesia. Front Neural Circuits 2020; 14:55. [PMID: 32973462 PMCID: PMC7461971 DOI: 10.3389/fncir.2020.00055] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 07/27/2020] [Indexed: 01/17/2023] Open
Abstract
Background: Monochromatic blue light (MBL), with a wavelength between 400–490 nm, can regulate non-image-forming (NIF) functions of light in the central nervous system. The suprachiasmatic nucleus (SCN) in the brain is involved in the arousal-promoting response to blue light in mice. Animal and human studies showed that the responsiveness of the brain to visual stimuli is partly preserved under general anesthesia. Therefore, this study aimed to investigate whether MBL promotes arousal from sevoflurane anesthesia via activation of the SCN in mice. Methods: The induction and emergence time of sevoflurane anesthesia under MBL (460 nm and 800 lux) exposure was measured. Cortical electroencephalograms (EEGs) were recorded and the burst-suppression ratio (BSR) was calculated under MBL during sevoflurane anesthesia. The EEGs and local field potential (LFP) recordings with or without locally electrolytic ablated bilateral SCN were used to further explore the role of SCN in the arousal-promoting effect of MBL under sevoflurane anesthesia. Immunofluorescent staining of c-Fos was conducted to reveal the possible downstream mechanism of SCN activation. Results: Unlike the lack of effect on the induction time, MBL shortened the emergence time and the EEG recordings showed cortical arousal during the recovery period. MBL resulted in a significant decrease in BSR and a marked increase in EEG power at all frequency bands except for the spindle band during 2.5% sevoflurane anesthesia. MBL exposure under sevoflurane anesthesia enhances the neuronal activity of the SCN. These responses to MBL were abolished in SCN lesioned (SCNx) mice. MBL evoked a high level of c-Fos expression in the prefrontal cortex (PFC) and lateral hypothalamus (LH) compared to polychromatic white light (PWL) under sevoflurane anesthesia, while it exerted no effect on c-Fos expression in the ventrolateral preoptic area (VLPO) and locus coeruleus (LC) c-Fos expression. Conclusions: MBL promotes behavioral and electroencephalographic arousal from sevoflurane anesthesia via the activation of the SCN and its associated downstream wake-related nuclei. The clinical implications of this study warrant further study.
Collapse
Affiliation(s)
- Daiqiang Liu
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jiayan Li
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jiayi Wu
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jiaqi Dai
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, China
| | - Xinfeng Chen
- Chinese Institute for Brain Research (CIBR), ZGC Life Science Park, Beijing, China
| | - Yujie Huang
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Shuang Zhang
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Bo Tian
- Department of Neurobiology, Tongji Medical School, Huazhong University of Science and Technology, Wuhan, China.,Key Laboratory of Neurological Diseases, Ministry of Education, Wuhan, China
| | - Wei Mei
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| |
Collapse
|
11
|
Liu D, Chen X, Huang Y, Zhang S, Wu J, Li J, Wang D, Tian B, Mei W. Acute continuous nocturnal light exposure decreases BSR under sevoflurane anesthesia in C57BL/6J mice: possible role of differentially spared light-sensitive pathways under anesthesia. Am J Transl Res 2020; 12:2843-2859. [PMID: 32655814 PMCID: PMC7344097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 05/18/2020] [Indexed: 06/11/2023]
Abstract
Brain responses to external stimuli such as light are preserved under general anesthesia. In nocturnal animals, acute light exposure can induce sleep, and acute dark can increase wakefulness. This study aims to investigate the effect of acute continuous nocturnal light exposure (ACNLE) on burst-suppression patterns under sevoflurane anesthesia using electroencephalogram (EEG) monitoring in mice. We set the initial sevoflurane dose to 2.0% and increased it by 0.5% every 20 min until it reached 4.0%. Burst-suppression ratio (BSR), EEG power and quantitative burst analysis were used to assess the effects of ACNLE on burst suppression patterns under sevoflurane anesthesia. Blood serum corticosterone measurement and c-Fos immunofluorescent staining of the suprachiasmatic nucleus (SCN) and ventrolateral preoptic nucleus (VLPO) were used to demonstrate the biological consequence induced by ACNLE. Compared to darkness, ACNLE caused significant changes in EEG power and decrease of BSR at 2.5%, 3.0% and 3.5% sevoflurane. ACNLE was also associated with an increase in burst duration and burst frequency as well as a decrease in burst maximum peak-to-peak amplitude and burst power in the beta (15-25 Hz) and gamma (25-80 Hz) bands. ACNLE increased the concentration of serum corticosterone and the expression of c-Fos in the SCN, while not changed c-Fos expression in the VLPO. These results demonstrated that ACNLE influences the BSR under sevoflurane anesthesia, possibly by activating light-sensitive nonvisual pathways including SCN and increasing of peripheral serum corticosterone levels.
Collapse
Affiliation(s)
- Daiqiang Liu
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and TechnologyWuhan 430030, Hubei Province, China
| | - Xinfeng Chen
- Chinese Institute for Brain ResearchBeijing (CIBR) No. 26 Science Park Road, ZGC Life Science Park, Changping District, Beijing 100085, China
| | - Yujie Huang
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and TechnologyWuhan 430030, Hubei Province, China
| | - Shuang Zhang
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and TechnologyWuhan 430030, Hubei Province, China
| | - Jiayi Wu
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and TechnologyWuhan 430030, Hubei Province, China
| | - Jiayan Li
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and TechnologyWuhan 430030, Hubei Province, China
| | - Dan Wang
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and TechnologyWuhan 430030, Hubei Province, China
| | - Bo Tian
- Department of Neurobiology, Tongji Medical School, Huazhong University of Science and TechnologyWuhan 430030, Hubei Province, China
- Key Laboratory of Neurological Diseases, Ministry of Education13 Hangkong Road, Wuhan 430030, Hubei Province, China
| | - Wei Mei
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and TechnologyWuhan 430030, Hubei Province, China
| |
Collapse
|
12
|
Reimann HM, Niendorf T. The (Un)Conscious Mouse as a Model for Human Brain Functions: Key Principles of Anesthesia and Their Impact on Translational Neuroimaging. Front Syst Neurosci 2020; 14:8. [PMID: 32508601 PMCID: PMC7248373 DOI: 10.3389/fnsys.2020.00008] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 01/27/2020] [Indexed: 12/11/2022] Open
Abstract
In recent years, technical and procedural advances have brought functional magnetic resonance imaging (fMRI) to the field of murine neuroscience. Due to its unique capacity to measure functional activity non-invasively, across the entire brain, fMRI allows for the direct comparison of large-scale murine and human brain functions. This opens an avenue for bidirectional translational strategies to address fundamental questions ranging from neurological disorders to the nature of consciousness. The key challenges of murine fMRI are: (1) to generate and maintain functional brain states that approximate those of calm and relaxed human volunteers, while (2) preserving neurovascular coupling and physiological baseline conditions. Low-dose anesthetic protocols are commonly applied in murine functional brain studies to prevent stress and facilitate a calm and relaxed condition among animals. Yet, current mono-anesthesia has been shown to impair neural transmission and hemodynamic integrity. By linking the current state of murine electrophysiology, Ca2+ imaging and fMRI of anesthetic effects to findings from human studies, this systematic review proposes general principles to design, apply and monitor anesthetic protocols in a more sophisticated way. The further development of balanced multimodal anesthesia, combining two or more drugs with complementary modes of action helps to shape and maintain specific brain states and relevant aspects of murine physiology. Functional connectivity and its dynamic repertoire as assessed by fMRI can be used to make inferences about cortical states and provide additional information about whole-brain functional dynamics. Based on this, a simple and comprehensive functional neurosignature pattern can be determined for use in defining brain states and anesthetic depth in rest and in response to stimuli. Such a signature can be evaluated and shared between labs to indicate the brain state of a mouse during experiments, an important step toward translating findings across species.
Collapse
Affiliation(s)
- Henning M. Reimann
- Berlin Ultrahigh Field Facility (B.U.F.F.), Max-Delbrück Center for Molecular Medicine, Helmholtz Association of German Research Centers (HZ), Berlin, Germany
| | - Thoralf Niendorf
- Berlin Ultrahigh Field Facility (B.U.F.F.), Max-Delbrück Center for Molecular Medicine, Helmholtz Association of German Research Centers (HZ), Berlin, Germany
- Experimental and Clinical Research Center, A Joint Cooperation Between the Charité Medical Faculty and the Max-Delbrück Center for Molecular Medicine, Berlin, Germany
| |
Collapse
|