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Cerebral microvascular network geometry changes in response to functional stimulation

Liis Lindvere, Rafal Janik, Adrienne Dorr, David Chartash, Bhupinder Sahota, John G. Sled, Bojana Stefanovic
2013 NeuroImage  
The changes in the geometry of this network were then tracked, over time, in the course of electrical stimulation of the contralateral forepaw.  ...  We developed a custom two photon fluorescence microscopy acquisition and analysis to obtain 3D maps of neuronal activation-induced changes in the geometry of the microvascular network of the primary somatosensory  ...  Martijn E. van Raaij for his contribution to image analysis and image acquisition optimization and Dr. Lakshminarayan V. Chinta for his contributions to image analysis.  ... 
doi:10.1016/j.neuroimage.2013.01.011 pmid:23353600 fatcat:es6braeclfbwjpftn7xuz4fp7i

Quantitative estimates of stimulation-induced perfusion response using two-photon fluorescence microscopy of cortical microvascular networks

Lakshminarayan V. Chinta, Liis Lindvere, Adrienne Dorr, Bhupinder Sahota, John G. Sled, Bojana Stefanovic
2012 NeuroImage  
The current methodology enables quantification of absolute perfusion associated with individual vessels of the cortical microvascular bed and its changes in response to functional stimulation and thereby  ...  to functional stimulation.  ...  Acknowledgments The authors would like to thank Rafal Janik for assistance in the preparation of figures. This work was supported by the Canadian Institutes of Health Research (CIHR).  ... 
doi:10.1016/j.neuroimage.2012.04.009 pmid:22521258 fatcat:unpvxvfxqvhlbgyp6joingvgqy

Modeling of Cerebral Oxygen Transport Based on In vivo Microscopic Imaging of Microvascular Network Structure, Blood Flow, and Oxygenation

Louis Gagnon, Amy F. Smith, David A. Boas, Anna Devor, Timothy W. Secomb, Sava Sakadžić
2016 Frontiers in Computational Neuroscience  
Oxygen is delivered to brain tissue by a dense network of microvessels, which actively control cerebral blood flow (CBF) through vasodilation and contraction in response to changing levels of neural activity  ...  models of cerebral hemodynamics and oxygen transport based on realistic three-dimensional microvascular networks.  ...  Oxygen is delivered to brain tissue by a dense network of microvessels, which actively control cerebral blood flow (CBF) through vasodilation and contraction in response to changing levels of neural activity  ... 
doi:10.3389/fncom.2016.00082 pmid:27630556 pmcid:PMC5006088 fatcat:clfqug3nwbhjpalfdw32usyeoq

Diverse Functions of Pericytes in Cerebral Blood Flow Regulation and Ischemia

Francisco Fernandez-Klett, Josef Priller
2015 Journal of Cerebral Blood Flow and Metabolism  
Here, we provide evidence that microvascular pericytes modulate cerebral blood flow in response to neuronal activity ('functional hyperemia').  ...  Besides their role in neurovascular coupling, pericytes are responsive to brain damage.  ...  functional units (even if the geometry and topology of the network does not predict the boundaries, as discussed above).  ... 
doi:10.1038/jcbfm.2015.60 pmid:25853910 pmcid:PMC4640260 fatcat:kt6seyqmczfshlues5capwcmp4

Quantifying the Microvascular Origin of BOLD-fMRI from First Principles with Two-Photon Microscopy and an Oxygen-Sensitive Nanoprobe

L. Gagnon, S. Sakad i, F. Lesage, J. J. Musacchia, J. Lefebvre, Q. Fang, M. A. Yucel, K. C. Evans, E. T. Mandeville, J. Cohen-Adad, J. R. Polimeni, M. A. Yaseen (+6 others)
2015 Journal of Neuroscience  
However, the BOLD signal reflects changes in blood volume and oxygenation rather than neuronal activity per se.  ...  The blood oxygenation level-dependent (BOLD) contrast is widely used in functional magnetic resonance imaging (fMRI) studies aimed at investigating neuronal activity.  ...  The MRF dictionary used in this case was constructed from a Monte Carlo fMRI model with simplified vascular geometry and oxygen content.  ... 
doi:10.1523/jneurosci.3555-14.2015 pmid:25716864 pmcid:PMC4339366 fatcat:js2kiyatrrezndxyodj25k67hq

Model of the Transient Neurovascular Response Based on Prompt Arterial Dilation

Jung Hwan Kim, Reswanul Khan, Jeffrey K Thompson, David Ress
2013 Journal of Cerebral Blood Flow and Metabolism  
Brief neural stimulation results in a stereotypical pattern of vascular and metabolic response that is the basis for popular brainimaging methods such as functional magnetic resonance imagine.  ...  Using six parameters, the model successfully fit 161/166 measured extravascular oxygen time courses obtained for brief visual stimulation in cat cerebral cortex.  ...  MATERIALS AND METHODS Transport Model A one-dimensional (1D) cylindrical geometry is employed to represent a single, stereotypical element of the microvascular network in cerebral cortex, a 'vascular  ... 
doi:10.1038/jcbfm.2013.90 pmid:23756690 pmcid:PMC3764388 fatcat:3vu4ctkpdrehvfpo46istvm2za

Cortical depth-specific microvascular dilation underlies laminar differences in blood oxygenation level-dependent functional MRI signal

P. Tian, I. C. Teng, L. D. May, R. Kurz, K. Lu, M. Scadeng, E. M. C. Hillman, A. J. De Crespigny, H. E. D'Arceuil, J. B. Mandeville, J. J. A. Marota, B. R. Rosen (+5 others)
2010 Proceedings of the National Academy of Sciences of the United States of America  
In the present study, we used this technology to examine microvascular responses to sensory stimulation down to 550 μm below the cortical surface in the rat primary somatosensory cortex (SI).  ...  However, in addition to local neurovascular coupling, vascular responses can propagate within the arteriolar/capillary networks (3, 9, 10) .  ...  Previous studies in vivo have demonstrated that both arterioles and capillaries can change diameter in response to stimulation (1, 2, 4, 36) .  ... 
doi:10.1073/pnas.1006735107 pmid:20696904 pmcid:PMC2930564 fatcat:cmufenqat5hg5lqpczetanpgre

Vascular density and distribution in neocortex

Franca Schmid, Matthew J.P. Barrett, Patrick Jenny, Bruno Weber
2017 NeuroImage  
In this review, we provide a detailed characterization of the most relevant anatomical and functional features of the cortical vasculature.  ...  Much of the information processing that leads to these behaviors is performed in neocortical circuits that span throughout the six layers of the cortex.  ...  of changes of tissue pO2 at multiple cortical depths in response to electrical stimulation of the rat whisker pad.  ... 
doi:10.1016/j.neuroimage.2017.06.046 pmid:28669910 fatcat:ipntassnpjflbgqsdrt7ssvoh4

Erythrocytes: Oxygen Sensors and Modulators of Vascular Tone

Mary L. Ellsworth, Christopher G. Ellis, Daniel Goldman, Alan H. Stephenson, Hans H. Dietrich, Randy S. Sprague
2009 Physiology  
Through oxygen-dependent release of the vasodilator ATP, the mobile erythrocyte plays a fundamental role in matching microvascular oxygen supply with local tissue oxygen demand.  ...  Our understanding of the impact of this novel control mechanism will rely on the integration of in vivo experiments and computational models. 1548-9213/09 8.00 ©2009 Int. Union Physiol. Sci./Am.  ...  Studies in cerebral microvessels have delineated the specific receptors present and the vasoactive response to their stimulation.  ... 
doi:10.1152/physiol.00038.2008 pmid:19364913 pmcid:PMC2725440 fatcat:qe3ljs67tzhzbmxcfg3qweuzoa

Microvascular Tissue Engineering—A Review

Jernej Vajda, Marko Milojević, Uroš Maver, Boštjan Vihar
2021 Biomedicines  
In this review, we present the state of the art in the field of microvascular tissue engineering and demonstrate the challenges for future research in various sections of the field.  ...  Tissue engineering and regenerative medicine have come a long way in recent decades, but the lack of functioning vasculature is still a major obstacle preventing the development of thicker, physiologically  ...  Increased microvascular network formation was detectable after around 10 h in the flow chamber. After 48 h, both the perfused network and the control network were evaluated.  ... 
doi:10.3390/biomedicines9060589 pmid:34064101 fatcat:22sas5jnyfd23oe5uqjzyjlqny

The Effects of Transit Time Heterogeneity on Brain Oxygenation during Rest and Functional Activation

Peter M Rasmussen, Sune N Jespersen, Leif Østergaard
2015 Journal of Cerebral Blood Flow and Metabolism  
We show that the incorporation of realistic reductions in CTH during functional hyperemia improves model fits to dynamic blood flow and oxygenation changes acquired during functional activation in a literature  ...  Our results support earlier observations that oxygen diffusion properties seemingly change during various physiologic stimuli, and posit that this phenomenon is related to parallel changes in capillary  ...  ACKNOWLEDGMENTS The authors thank Hugo Angleys for fruitful discussions and David Boas for helpful comments and suggestions to our manuscript.  ... 
doi:10.1038/jcbfm.2014.213 pmid:25492112 pmcid:PMC4348381 fatcat:udkg5j5n6fh5jdu27ibdq3stiu

Simulation of angiogenesis in three dimensions: Application to cerebral cortex

Jonathan P. Alberding, Timothy W. Secomb, Philip K. Maini
2021 PLoS Computational Biology  
At the microvascular level, network geometry is not predetermined, but emerges as a result of biological responses of each vessel to the stimuli that it receives.  ...  The model provides insights into the effects of deficits in vascular response mechanisms, and can be used to generate physiologically realistic microvascular network structures.  ...  Furthermore, chronic changes in vascular tone have been shown to lead to corresponding changes in structural vessel diameters [66, 67] , which implies a role for conducted responses in structural remodeling  ... 
doi:10.1371/journal.pcbi.1009164 pmid:34170925 fatcat:tlistttqvbh5xfffzaskmrbzti

Measuring the Interaction Between the Macro- and Micro-Vasculature

Rachel E. Climie, Antonio Gallo, Dean S. Picone, Nicole Di Lascio, Thomas T. van Sloten, Andrea Guala, Christopher C. Mayer, Bernhard Hametner, Rosa Maria Bruno
2019 Frontiers in Cardiovascular Medicine  
However, in response to aging, hypertension, and other disease states, arterial stiffening limits the buffering capacity of the elastic arteries, thus exposing the microvasculature to increased pulsatile  ...  Structural and functional dysfunction in both the macro- and microvasculature are a feature of essential hypertension.  ...  WIA was used to assess changes in the cerebral vasomotor tone as a consequence of a hypercapnia status, which is known to alter cerebral resistance.  ... 
doi:10.3389/fcvm.2019.00169 pmid:31824963 pmcid:PMC6882776 fatcat:f6u4vm33qvaydbsl54afb6edjy

A model for transient oxygen delivery in cerebral cortex

David Ress
2009 Frontiers in Neuroenergetics  
The results give insight into the dynamics of cerebral oxygen transfer, and can serve as the starting point to understand BOLD fMRI measurements. with diffusion in a compartmental geometry.  ...  oxygen is delivered to the cortex in response to brief periods of neural activity.  ...  ACKNOWLEDGEMENT The authors thank Ralph Freeman for providing the experimental data used in this work. SUPPLEMENTARY MATERIAL  ... 
doi:10.3389/neuro.14.003.2009 pmid:19597566 pmcid:PMC2709201 fatcat:6ygdn43hgrhy3ig7vreo3dzxpi

Advances in on-chip vascularization

Kristina Haase, Roger D Kamm
2017 Regenerative Medicine  
Microfluidic design can cleverly control geometry, biochemical gradients and mechanical stimuli, such as shear and interstitial flow, to more closely mimic in vivo conditions.  ...  In vitro vascular networks are generated by two distinct approaches: via endothelial-lined patterned channels, or by selfassembled networks.  ...  and mechanisms behind changes in microvasculature structure and function.  ... 
doi:10.2217/rme-2016-0152 pmid:28318376 pmcid:PMC5574321 fatcat:gafpkg5zanc7nc5cx37aem6gdi
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