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Frequency-dependent neural activity, CBF, and BOLD fMRI to somatosensory stimuli in isoflurane-anesthetized rats

Tae Kim, Kazuto Masamoto, Mitsuhiro Fukuda, Alberto Vazquez, Seong-Gi Kim
2010 NeuroImage  
Inhalation anesthetics (e.g. isoflurane) are preferable for longitudinal fMRI experiments in the same animals.  ...  CBF (using arterial spin labeling: CBF ASL ) and blood oxygenation level dependent (BOLD) fMRI responses were measured at 9.4 T for four stimulus frequencies (1.5-12 Hz).  ...  Iwao Kanno and Takayuki Obata for valuable discussions on the vascular responses and Dr. Daniel Simons for discussion on neural adaption.  ... 
doi:10.1016/j.neuroimage.2010.03.064 pmid:20350603 pmcid:PMC2883664 fatcat:w64wn4vwtndn3pizluh36rpfoe

Neural Origin of Spontaneous Hemodynamic Fluctuations in Rats under Burst-Suppression Anesthesia Condition

X. Liu, X.-H. Zhu, Y. Zhang, W. Chen
2010 Cerebral Cortex  
Functional magnetic resonance imaging (fMRI) was used to image spontaneous blood oxygen level--dependent (BOLD) signals under the same anesthesia conditions and showed similar BOLD "bumps" and dependence  ...  cortical regions of rats with isoflurane-induced burst--suppression EEG activity.  ...  The authors thank Dr Nanyin Zhang, Dr Fei Du, and Ms Xiao Wang for technical assistance and discussion, and Dr Kamil Ugurbil for support. Conflict of Interest : None declared.  ... 
doi:10.1093/cercor/bhq105 pmid:20530220 pmcid:PMC3020581 fatcat:dz5qj3ytvffxxprbbs2wh44kbu

Noise and non-neuronal contributions to the BOLD signal: applications to and insights from animal studies

Shella D. Keilholz, Wen-Ju Pan, Jacob Billings, Maysam Nezafati, Sadia Shakil
2017 NeuroImage  
The BOLD signal reflects hemodynamic events within the brain, which in turn are driven by metabolic changes and neural activity.  ...  However, the link between BOLD changes and neural activity is indirect and can be influenced by a number of non-neuronal processes.  ...  Acknowledgments The authors would like to thank Anzar Abbas, Hyun Koo Chung, and Amrit Kashyap for helpful discussions.  ... 
doi:10.1016/j.neuroimage.2016.12.019 pmid:28017922 pmcid:PMC5481494 fatcat:cfjnbrsikzhglpfgml4mmikq24

Hemodynamic-based Mapping of Neural Activity in Medetomidine-sedated Rats using a 1.5T Compact Magnetic Resonance Imaging System: A Preliminary Study

Masayuki YAMADA, Kazuki TAKANO, Yuki KAWAI, Ryoichi KATO
2015 Magnetic Resonance in Medical Sciences  
We investigated the potential of such systems in functional MR imaging (fMRI) of somatosensory cortex activity elicited by forepaw stimulation in medetomidine-sedated rats.  ...  in hemodynamic-based fMRI in preclinical and translational research.  ...  (rCBF) following neural activation in the brain. 5 However, the high performance demanded of MR imaging systems with ultrahigh fields in BOLD-based fMRI greatly increases the cost and size of these  ... 
doi:10.2463/mrms.2014-0084 pmid:25833273 fatcat:is5coowwvbevhntckpz7gisz2m

Technical and Conceptual Considerations for Performing and Interpreting Functional MRI Studies in Awake Rats

Marcelo Febo
2011 Frontiers in Psychiatry  
Our laboratory has used imaging to investigate brain activation in awake rats following cocaine administration and during the presentation of lactation-associated sensory stimuli.  ...  The relatively good spatial and temporal resolution and the ever-growing database on the biological and biophysical basis of the blood oxygen level dependent (BOLD) signal make it a unique technique in  ...  The percent change in CBF and BOLD in response to CO 2 , however, is lower in anesthetized rats (Sicard et al., 2003) .  ... 
doi:10.3389/fpsyt.2011.00043 pmid:21808625 pmcid:PMC3137945 fatcat:fu5tf4mi2fgapdru4nxyneywvi

Hemodynamic and metabolic changes induced by cocaine in anesthetized rat observed with multimodal functional MRI

Karl F. Schmidt, Marcelo Febo, Qiang Shen, Feng Luo, Kenneth M. Sicard, Craig F. Ferris, Elliot A. Stein, Timothy Q. Duong
2006 Psychopharmacology  
imaging (fMRI) mapping signals, independent of neural activity.  ...  Materials and methods: BOLD and CBF fMRI was performed, and changes in CMRO 2 were estimated using the BOLD biophysical model.  ...  All experiments were performed in accordance with guidelines for the care and use of mammals in neuroscience and behavioral research (National Research Council 2003) and in compliance with the laws of  ... 
doi:10.1007/s00213-006-0319-1 pmid:16550388 pmcid:PMC2949961 fatcat:lwaatq34x5g4nbptvknqpgwwsm

BOLD study of stimulation-induced neural activity and resting-state connectivity in medetomidine-sedated rat

Fuqiang Zhao, Tiejun Zhao, Lei Zhou, Qiulin Wu, Xiaoping Hu
2008 NeuroImage  
Since stimulation-induced fMRI signal is anesthesia-dependent and its characteristics in rats under medetomidine are not fully elucidated, the blood oxygenation level dependent (BOLD) fMRI response to  ...  Robust activations in contralateral primary somatosensory cortex (SI) and thalamus were observed and peaked at the stimulus frequency of 9 Hz.  ...  Acknowledgements Supported by NIH (RO1EB002009), the National Science Foundation (BES 0401627) and Georgia Research Alliance.  ... 
doi:10.1016/j.neuroimage.2007.07.063 pmid:17904868 pmcid:PMC2137163 fatcat:hpaqxpizuzfffmgj6hgzabg73q

An approach to probe some neural systems interaction by functional MRI at neural time scale down to milliseconds

S. Ogawa, T.-M. Lee, R. Stepnoski, W. Chen, X.-H. Zhu, K. Ugurbil
2000 Proceedings of the National Academy of Sciences of the United States of America  
In the cerebellum of anesthetized rats, the regional CBF increase was also shown to be proportional to the product of the frequency of stimulation and the strength of the evoked local field potential near  ...  Both CBF and BOLD signals of fMRI are quite slow to respond to variations in neuronal activity because they evolve in seconds rather than in milliseconds (17) (18) (19) .  ...  In the cerebellum of anesthetized rats, the regional CBF increase was also shown to be proportional to the product of the frequency of stimulation and the strength of the evoked local field potential near  ... 
doi:10.1073/pnas.97.20.11026 pmid:11005873 pmcid:PMC27142 fatcat:wtm2wuf3tnfodprhe3ikdwdzg4

Longitudinal, transcranial measurement of functional activation in the rat brain by diffuse correlation spectroscopy

Igor Blanco, Peyman Zirak, Tanja Dragojević, Clara Castellvi, Turgut Durduran, Carles Justicia
2017 Neurophotonics  
We were able to detect changes in CBF in the somatosensory cortex by using a model of electrical forepaw stimulation in rats.  ...  The overall results obtained with transcutaneous DCS demonstrates that it can be utilized in longitudinal studies safely and reproducibly to locate changes in CBF induced by neural activity in the small  ...  Acknowledgments The project was funded by Fundació CELLEX Barcelona, Ministerio de Economía y Competitividad (PHOTODEMENTIA, DPI2015-64358-C2-1-R and DPI2015-64358-C2-2-R, PHOTOSTROKE), the "Severo Ochoa  ... 
doi:10.1117/1.nph.4.4.045006 pmid:29226175 pmcid:PMC5715584 fatcat:sexcxvcg2zefhmttbhmk2uejni

Neural and Hemodynamic Responses to Optogenetic and Sensory Stimulation in the Rat Somatosensory Cortex

Bistra Iordanova, Alberto L Vazquez, Alexander J Poplawsky, Mitsuhiro Fukuda, Seong-Gi Kim
2015 Journal of Cerebral Blood Flow and Metabolism  
oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) during optogenetic and sensory stimulation.  ...  For that purpose, rats expressing channelrhodopsin (ChR2) specific to excitatory glutamatergic neurons were used to measure neural activity, blood flow, hemoglobin-based optical intrinsic signal, and blood  ...  ACKNOWLEDGMENTS The authors would like to thank Ping Wang and Francesca Nicholls for technical assistance, Michel Modo for instrumentation access, and Owen Smith for the artist rendering of the experimental  ... 
doi:10.1038/jcbfm.2015.10 pmid:25669905 pmcid:PMC4640245 fatcat:2u6istfb7fb5jjcbttkgevg3uq

Stimulus frequency dependence of blood oxygenation level-dependent functional magnetic resonance imaging signals in the somatosensory cortex of rats

Ikuhiro Kida, Toru Yamamoto
2008 Neuroscience research  
Our results show that stimulus duration has little influence on the stimulus frequency dependence of BOLD signals in the rat somatosensory model.  ...  To clarify whether the stimulus frequency dependence of BOLD signals depends on the stimulus duration, we measured BOLD signals at 7 T with short and long stimulus durations for stimulating rat forepaw  ...  This study was supported by grants from the Akiyama Foundation; Takeda Science Foundation; Mitsubishi Foundation (to I.K.); and Japanese Ministry of Education, Science, Sports and Culture (Grant Number  ... 
doi:10.1016/j.neures.2008.05.006 pmid:18602178 fatcat:um2fj7spn5dszpfefsrezfhjii

High-resolution functional magnetic resonance imaging of the animal brain

Seong-Gi Kim, Kamil Ugurbil
2003 Methods  
Since fMRI measures a change in secondary hemodynamic responses induced by neural activity, it is critical to understand the principles and potential pitfalls of fMRI techniques.  ...  Tissue-specific signal change is close to the site of neural activity, while signals from large vessels can be distant from the actual active site.  ...  Acknowledgments This work is supported by the National Institutes of Health (NS38295, NS40719, and NS44589), the McKnight Foundation, and the Keck Foundation.  ... 
doi:10.1016/s1046-2023(03)00005-7 pmid:12695101 fatcat:7kqffgpk7re7xnilxr3ukd5hui

Assessment of brain responses to innocuous and noxious electrical forepaw stimulation in mice using BOLD fMRI

Simone C. Bosshard, Christof Baltes, Matthias T. Wyss, Thomas Mueggler, Bruno Weber, Markus Rudin
2010 Pain  
Functional magnetic resonance imaging (fMRI) using the blood oxygen level-dependent (BOLD) contrast was used to study sensory processing in the brain of isoflurane-anesthetized mice.  ...  This study demonstrates the feasibility of a robust BOLD fMRI protocol to study nociceptive processing in isoflurane-anesthetized mice.  ...  Acknowledgments The authors thank the NCCR Neural Plasticity and Repair and the Swiss National Science Foundation for funding this project. There are no conflicts of interest to declare.  ... 
doi:10.1016/j.pain.2010.08.025 pmid:20851520 fatcat:5764hcdzenbkdfymgspaelbtve

Effects of the α2-adrenergic receptor agonist dexmedetomidine on neural, vascular and BOLD fMRI responses in the somatosensory cortex

Mitsuhiro Fukuda, Alberto L. Vazquez, Xiaopeng Zong, Seong-Gi Kim
2012 European Journal of Neuroscience  
unit activity, local field potential (LFP), cerebral blood flow (CBF), pial vessel diameter [indicative of cerebral blood volume (CBV)], and blood oxygenation level-dependent (BOLD) fMRI.  ...  Similarly, BOLD fMRI responses measured at 9.4 T were largest at a frequency of 10 Hz.  ...  Abbreviations BOLD, blood oxygenation level-dependent; CBF, cerebral blood flow; CBV, cerebral blood volume; DEX, dexmedetomidine; EEG, electroencephalography; fMRI, functional magnetic resonance imaging  ... 
doi:10.1111/ejn.12024 pmid:23106361 pmcid:PMC3538949 fatcat:j3qs2ojzf5ec7iczk5fcvzmwbi

The (Un)Conscious Mouse as a Model for Human Brain Functions: Key Principles of Anesthesia and Their Impact on Translational Neuroimaging

Henning M. Reimann, Thoralf Niendorf
2020 Frontiers in Systems Neuroscience  
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.  ...  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.  ...  Nikoloz Sirmpilatze (Functional Imaging Laboratory, Deutsches Primatenzentrum, Göttingen, Germany) for valuable discussions, reading and commenting on the manuscript.  ... 
doi:10.3389/fnsys.2020.00008 pmid:32508601 pmcid:PMC7248373 fatcat:eelkqgl3ybbchpbxeiamp54jea
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