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Sneed SE, Scheulin KM, Kaiser EE, Fagan MM, Jurgielewicz BJ, Waters ES, Spellicy SE, Duberstein KJ, Platt SR, Baker EW, Stice SL, Kinder HA, West FD. Magnetic Resonance Imaging and Gait Analysis Indicate Similar Outcomes Between Yucatan and Landrace Porcine Ischemic Stroke Models. Front Neurol 2021; 11:594954. [PMID: 33551956 PMCID: PMC7859633 DOI: 10.3389/fneur.2020.594954] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 12/21/2020] [Indexed: 12/21/2022] Open
Abstract
The Stroke Therapy Academic Industry Roundtable (STAIR) has recommended that novel therapeutics be tested in a large animal model with similar anatomy and physiology to humans. The pig is an attractive model due to similarities in brain size, organization, and composition relative to humans. However, multiple pig breeds have been used to study ischemic stroke with potentially differing cerebral anatomy, architecture and, consequently, ischemic stroke pathologies. The objective of this study was to characterize brain anatomy and assess spatiotemporal gait parameters in Yucatan (YC) and Landrace (LR) pigs pre- and post-stroke using magnetic resonance imaging (MRI) and gait analysis, respectively. Ischemic stroke was induced via permanent middle cerebral artery occlusion (MCAO). MRI was performed pre-stroke and 1-day post-stroke. Structural and diffusion-tensor sequences were performed at both timepoints and analyzed for cerebral characteristics, lesion diffusivity, and white matter changes. Spatiotemporal and relative pressure gait measurements were collected pre- and 2-days post-stroke to characterize and compare acute functional deficits. The results from this study demonstrated that YC and LR pigs exhibit differences in gross brain anatomy and gait patterns pre-stroke with MRI and gait analysis showing statistical differences in the majority of parameters. However, stroke pathologies in YC and LR pigs were highly comparable post-stroke for most evaluated MRI parameters, including lesion volume and diffusivity, hemisphere swelling, ventricle compression, caudal transtentorial and foramen magnum herniation, showing no statistical difference between the breeds. In addition, post-stroke changes in velocity, cycle time, swing percent, cadence, and mean hoof pressure showed no statistical difference between the breeds. These results indicate significant differences between pig breeds in brain size, anatomy, and motor function pre-stroke, yet both demonstrate comparable brain pathophysiology and motor outcomes post-stroke. The conclusions of this study suggest pigs of these different breeds generally show a similar ischemic stroke response and findings can be compared across porcine stroke studies that use different breeds.
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Affiliation(s)
- Sydney E Sneed
- Regenerative Bioscience Center, University of Georgia, Athens, GA, United States.,Department of Animal and Dairy Science, University of Georgia, Athens, GA, United States
| | - Kelly M Scheulin
- Regenerative Bioscience Center, University of Georgia, Athens, GA, United States.,Department of Animal and Dairy Science, University of Georgia, Athens, GA, United States.,Biomedical and Health Sciences Institute Neuroscience Program, University of Georgia, Athens, GA, United States
| | - Erin E Kaiser
- Regenerative Bioscience Center, University of Georgia, Athens, GA, United States.,Department of Animal and Dairy Science, University of Georgia, Athens, GA, United States.,Biomedical and Health Sciences Institute Neuroscience Program, University of Georgia, Athens, GA, United States
| | - Madison M Fagan
- Regenerative Bioscience Center, University of Georgia, Athens, GA, United States.,Department of Animal and Dairy Science, University of Georgia, Athens, GA, United States
| | - Brian J Jurgielewicz
- Regenerative Bioscience Center, University of Georgia, Athens, GA, United States.,Biomedical and Health Sciences Institute Neuroscience Program, University of Georgia, Athens, GA, United States
| | - Elizabeth S Waters
- Regenerative Bioscience Center, University of Georgia, Athens, GA, United States.,Department of Animal and Dairy Science, University of Georgia, Athens, GA, United States.,Biomedical and Health Sciences Institute Neuroscience Program, University of Georgia, Athens, GA, United States
| | - Samantha E Spellicy
- Regenerative Bioscience Center, University of Georgia, Athens, GA, United States.,Biomedical and Health Sciences Institute Neuroscience Program, University of Georgia, Athens, GA, United States
| | - Kylee J Duberstein
- Regenerative Bioscience Center, University of Georgia, Athens, GA, United States.,Department of Animal and Dairy Science, University of Georgia, Athens, GA, United States
| | - Simon R Platt
- Department of Small Animal Medicine and Surgery, University of Georgia, Athens, GA, United States
| | | | - Steven L Stice
- Regenerative Bioscience Center, University of Georgia, Athens, GA, United States.,Department of Animal and Dairy Science, University of Georgia, Athens, GA, United States.,Aruna Bio, Inc., Athens, GA, United States
| | - Holly A Kinder
- Regenerative Bioscience Center, University of Georgia, Athens, GA, United States.,Department of Animal and Dairy Science, University of Georgia, Athens, GA, United States.,Biomedical and Health Sciences Institute Neuroscience Program, University of Georgia, Athens, GA, United States
| | - Franklin D West
- Regenerative Bioscience Center, University of Georgia, Athens, GA, United States.,Department of Animal and Dairy Science, University of Georgia, Athens, GA, United States.,Biomedical and Health Sciences Institute Neuroscience Program, University of Georgia, Athens, GA, United States
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Lay CC, Frostig RD. Complete protection from impending stroke following permanent middle cerebral artery occlusion in awake, behaving rats. Eur J Neurosci 2014; 40:3413-21. [PMID: 25216240 DOI: 10.1111/ejn.12723] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Revised: 08/11/2014] [Accepted: 08/13/2014] [Indexed: 11/29/2022]
Abstract
Using a rodent model of ischemic stroke [permanent middle cerebral artery occlusion (pMCAO)], our laboratory has previously demonstrated that sensory-evoked cortical activation via mechanical single whisker stimulation treatment delivered under an anesthetized condition within 2 h of ischemic onset confers complete protection from impending infarct. There is a limited time window for this protection; rats that received the identical treatment at 3 h following ischemic onset lost neuronal function and sustained a substantial infarct. Rats in these studies, however, were anesthetized with sodium pentobarbital or isoflurane, whereas most human stroke patients are typically awake. To optimize our animal model, the present study examined, using functional imaging, histological, and behavioral analysis, whether self-induced sensorimotor stimulation is also protective in unrestrained, behaving rats that actively explore an enriched environment. Rats were revived from anesthesia either immediately or at 3 h after pMCAO, at which point they were allowed to freely explore an enriched environment. Rats that explored immediately after ischemic onset maintained normal cortical function and did not sustain infarct, even when their whiskers were clipped. Rats that were revived at 3 h post-pMCAO exhibited eliminated cortical function and sustained cortical infarct. Further, the data suggested that the level of individual active exploration could influence the outcome. Thus, early activation of the ischemic cortical area via unrestrained exploration resulted in protection from ischemic infarct, whereas late activation resulted in infarct, irrespective of the level of arousal or whisker-specific stimulation.
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Affiliation(s)
- Christopher C Lay
- Department of Neurobiology and Behavior, University of California, 2205 McGaugh Hall, Irvine, CA, 92697-4550, USA; The Center for the Neurobiology of Learning and Memory, University of California, Irvine, CA, USA; The Center for Hearing Research, University of California, Irvine, CA, USA
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3
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Bouts MJRJ, Tiebosch IACW, van der Toorn A, Hendrikse J, Dijkhuizen RM. Lesion development and reperfusion benefit in relation to vascular occlusion patterns after embolic stroke in rats. J Cereb Blood Flow Metab 2014; 34:332-8. [PMID: 24301289 PMCID: PMC3915211 DOI: 10.1038/jcbfm.2013.202] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Revised: 10/08/2013] [Accepted: 10/25/2013] [Indexed: 11/09/2022]
Abstract
Vascular occlusion sites largely determine the pattern of cerebral tissue damage and likelihood of subsequent reperfusion after acute ischemic stroke. We aimed to elucidate relationships between flow obstruction in segments of the internal carotid artery (ICA) and middle cerebral artery (MCA), and (1) profiles of acute ischemic lesions and (2) probability of subsequent beneficial reperfusion. Embolic stroke was induced by unilateral intracarotid blood clot injection in normotensive (n=53) or spontaneously hypertensive (n=20) rats, followed within 2 hours by magnetic resonance (MR) angiography (MRA), diffusion- (DWI) and perfusion-weighted magnetic resonance imaging (MRI) (PWI). In a subset of animals (n=9), MRI was repeated after 24 and 168 hours to determine the predictive value of the occlusion pattern on benefit of reperfusion. The extent of cerebral perfusion and diffusion abnormality was related to the pattern of flow obstruction in ICA and MCA segments. Hypertensive animals displayed significantly larger cortical perfusion lesions. Acute perfusion-diffusion lesion mismatches were detected in all animals that subsequently benefitted from reperfusion. Yet, the presence of an angiography-diffusion mismatch was more specific in predicting reperfusion benefit. Combination of DWI, PWI, and MRA exclusively informs on the impact of arterial occlusion profiles after acute ischemic stroke, which may improve prognostication and subsequent treatment decisions.
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Affiliation(s)
- Mark J R J Bouts
- 1] Biomedical MR Imaging and Spectroscopy Group, Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands [2] Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Ivo A C W Tiebosch
- Biomedical MR Imaging and Spectroscopy Group, Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Annette van der Toorn
- Biomedical MR Imaging and Spectroscopy Group, Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Jeroen Hendrikse
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Rick M Dijkhuizen
- Biomedical MR Imaging and Spectroscopy Group, Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands
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Lay CC, Davis MF, Chen-Bee CH, Frostig RD. Mild sensory stimulation protects the aged rodent from cortical ischemic stroke after permanent middle cerebral artery occlusion. J Am Heart Assoc 2012; 1:e001255. [PMID: 23130160 PMCID: PMC3487352 DOI: 10.1161/jaha.112.001255] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Accepted: 06/15/2012] [Indexed: 11/16/2022]
Abstract
BACKGROUND Accumulated research has shown that the older adult brain is significantly more vulnerable to stroke than the young adult brain. Although recent evidence in young adult rats demonstrates that single-whisker stimulation can result in complete protection from ischemic damage after permanent middle cerebral artery occlusion (pMCAO), it remains unclear whether the same treatment would be effective in older animals. METHODS AND RESULTS Aged rats (21 to 24 months of age) underwent pMCAO and subsequently were divided into "treated" and "untreated" groups. Treated aged rats received intermittent single-whisker stimulation during a 120-minute period immediately after pMCAO, whereas untreated aged rats did not. These animals were assessed using a battery of behavioral tests 1 week before and 1 week after pMCAO, after which their brains were stained for infarct. An additional treated aged group and a treated young adult group also were imaged with functional imaging. Results demonstrated that the recovery of treated aged animals was indistinguishable from that of the treated young adult animals. Treated aged rats had fully intact sensorimotor behavior and no infarct, whereas untreated aged rats were impaired and sustained cortical infarct. CONCLUSIONS Taken together, our results confirm that single-whisker stimulation is protective in an aged rodent pMCAO model, despite age-associated stroke vulnerability. These findings further suggest potential for translation to the more clinically relevant older adult human population. (J Am Heart Assoc. 2012;1:e001255 doi: 10.1161/JAHA.112.001255.).
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Affiliation(s)
- Christopher C Lay
- Department of Neurobiology and Behavior, Irvine, CA (C.C.L., M.F.D., C.H.C.-B., R.D.F.) ; The Center for the Neurobiology of Learning and Memory, Irvine, CA (C.C.L., M.F.D., C.H.C.-B., R.D.F.) ; The Center for Hearing Research, University of California, Irvine, CA (C.C.L, R.D.F.)
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Mild sensory stimulation reestablishes cortical function during the acute phase of ischemia. J Neurosci 2011; 31:11495-504. [PMID: 21832179 DOI: 10.1523/jneurosci.1741-11.2011] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
When delivered within 1 and in most cases 2 h of permanent middle cerebral artery occlusion (pMCAO), mild sensory stimulation (intermittent single whisker stimulation) was shown to be completely neuroprotective 24 h after pMCAO in a rodent model of ischemic stroke, according to assessment with multiple techniques (Lay et al., 2010). The acute effect of stimulation treatment on the ischemic cortex, however, has yet to be reported. Here we characterize cortical function and perfusion during the 120 min whisker stimulation period in four experimental groups with treatment initiated 0, 1, 2 (protected groups), or 3 h (unprotected group) post-pMCAO using multiple techniques. According to functional imaging, a gradual return of evoked whisker functional representation to baseline levels was initiated with treatment onset and completed within the treatment period. Evoked neuronal activity and reperfusion to the ischemic area also showed a gradual recovery in protected animals. Surprisingly, a similar recovery profile was observed in response to treatment in all protected animals, regardless of treatment onset time. Nonstimulated pMCAO control group data demonstrate that reperfusion is not spontaneous. This makes the complete protection observed in the majority of animals stimulated at 2 h post-pMCAO even more surprising, as these animals recovered despite having been in a severely ischemic state for two full hours. In summary, when delivered within a 2 h window post-pMCAO, whisker stimulation treatment initiated reperfusion and a gradual recovery of cortical function that was completed or nearly completed within the treatment period.
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Senda DM, Franzin S, Mori MA, Oliveira RMWD, Milani H. Acute, post-ischemic sensorimotor deficits correlate positively with infarct size but fail to predict its occurrence and magnitude after middle cerebral artery occlusion in rats. Behav Brain Res 2011; 216:29-35. [DOI: 10.1016/j.bbr.2010.06.026] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2010] [Revised: 06/13/2010] [Accepted: 06/18/2010] [Indexed: 10/19/2022]
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7
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Boyko M, Zlotnik A, Gruenbaum BF, Gruenbaum SE, Ohayon S, Goldsmith T, Kotz R, Leibowitz A, Sheiner E, Shapira Y, Teichberg VI. An experimental model of focal ischemia using an internal carotid artery approach. J Neurosci Methods 2010; 193:246-53. [PMID: 20817031 DOI: 10.1016/j.jneumeth.2010.08.026] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2010] [Revised: 08/26/2010] [Accepted: 08/27/2010] [Indexed: 10/19/2022]
Abstract
Animal models of cerebral ischemia represent an important contribution to both our understanding of stroke mechanism and the development of new therapies. The technique of MCAO (middle cerebral artery occlusion) via ECA (external carotid artery) occlusion is widely utilized. Disruption of the ECA and its branches leads to impaired mastication and oral intake, post-surgical body weight loss, and poor neurological recovery which can possibly confound one's interpretation of rats' neurological outcome. Here, we developed a novel modified technique for MCAO without ligation or coagulation of the ECA and its branches using an approach via the internal carotid artery (ICA). In our modified technique, we perform an additional fixation of the filament in the ICA which improves the stability of the model and increases the homogeneity in stroke size. Compared with the original MCAO technique via the ECA, our modified technique via the ICA demonstrated decreased variability in the percent infarcted volume and brain edema, as well as a decreased mortality. Additionally, we observed that with our modified technique, rats gained more weight after surgery and there was less initial weight loss after the surgical preparation. Our new approach may serve as an effective model for stroke, and may lead to a better understanding of stoke pathophysiology and to the future development of new drugs and other neuroprotective agents.
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Affiliation(s)
- Matthew Boyko
- Division of Anesthesiology and Critical Care, Soroka Medical Center, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
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8
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Topological basis for the robust distribution of blood to rodent neocortex. Proc Natl Acad Sci U S A 2010; 107:12670-5. [PMID: 20616030 DOI: 10.1073/pnas.1007239107] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The maintenance of robust blood flow to the brain is crucial to the health of brain tissue. We examined the pial network of the middle cerebral artery, which distributes blood from the cerebral arteries to the penetrating arterioles that source neocortical microvasculature, to characterize how vascular topology may support such robustness. For both mice and rats, two features dominate the topology. First, interconnected loops span the entire territory sourced by the middle cerebral artery. Although the loops comprise <10% of all branches, they maintain the overall connectivity of the network after multiple breaks. Second, >80% of offshoots from the loops are stubs that end in a single penetrating arteriole, as opposed to trees with multiple penetrating arterioles. We hypothesize that the loops and stubs protect blood flow to the parenchyma from an occlusion in a surface vessel. To test this, we assayed the viability of tissue that was sourced by an individual penetrating arteriole following occlusion of a proximal branch in the surface loop. We observed that neurons remained healthy, even when occlusion led to a reduction in the local blood flow. In contrast, direct blockage of a single penetrating arteriole invariably led to neuronal death and formation of a cyst. Our results show that the surface vasculature functions as a grid for the robust allocation of blood in the event of vascular dysfunction. The combined results of the present and prior studies imply that the pial network reallocates blood in response to changing metabolic needs.
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Lay CC, Davis MF, Chen-Bee CH, Frostig RD. Mild sensory stimulation completely protects the adult rodent cortex from ischemic stroke. PLoS One 2010; 5:e11270. [PMID: 20585659 PMCID: PMC2890583 DOI: 10.1371/journal.pone.0011270] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2010] [Accepted: 05/31/2010] [Indexed: 01/20/2023] Open
Abstract
Despite progress in reducing ischemic stroke damage, complete protection remains elusive. Here we demonstrate that, after permanent occlusion of a major cortical artery (middle cerebral artery; MCA), single whisker stimulation can induce complete protection of the adult rat cortex, but only if administered within a critical time window. Animals that receive early treatment are histologically and behaviorally equivalent to healthy controls and have normal neuronal function. Protection of the cortex clearly requires reperfusion to the ischemic area despite permanent occlusion. Using blood flow imaging and other techniques we found evidence of reversed blood flow into MCA branches from an alternate arterial source via collateral vessels (inter-arterial connections), a potential mechanism for reperfusion. These findings suggest that the cortex is capable of extensive blood flow reorganization and more importantly that mild sensory stimulation can provide complete protection from impending stroke given early intervention. Such non-invasive, non-pharmacological intervention has clear translational potential.
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Affiliation(s)
- Christopher C. Lay
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, California, United States of America
- Center for the Neurobiology of Learning and Memory, University of California Irvine, Irvine, California, United States of America
| | - Melissa F. Davis
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, California, United States of America
- Center for the Neurobiology of Learning and Memory, University of California Irvine, Irvine, California, United States of America
| | - Cynthia H. Chen-Bee
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, California, United States of America
| | - Ron D. Frostig
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, California, United States of America
- Center for the Neurobiology of Learning and Memory, University of California Irvine, Irvine, California, United States of America
- Department of Biomedical Engineering, University of California Irvine, Irvine, California, United States of America
- * E-mail:
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Moldovan M, Constantinescu AO, Balseanu A, Oprescu N, Zagrean L, Popa-Wagner A. Sleep deprivation attenuates experimental stroke severity in rats. Exp Neurol 2010; 222:135-43. [PMID: 20045410 DOI: 10.1016/j.expneurol.2009.12.023] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Revised: 12/01/2009] [Accepted: 12/22/2009] [Indexed: 12/19/2022]
Abstract
Indirect epidemiological and experimental evidence suggest that the severity of injury during stroke is influenced by prior sleep history. The aim of our study was to test the effect of acute sleep deprivation on early outcome following experimental stroke. Young male Sprague-Dawley rats (n=20) were subjected to focal cerebral ischemia by reversible right middle cerebral artery occlusion (MCAO) for 90 min. In 10 rats, MCAO was performed just after 6-h of total sleep deprivation (TSD) by "gentle handling", whereas the other rats served as controls. Neurological function during the first week after stroke was monitored using a battery of behavioral tests investigating the asymmetry of sensorimotor deficit (tape removal test and cylinder test), bilateral sensorimotor coordination (rotor-rod and Inclined plane) and memory (T-maze and radial maze). Following MCAO, control rats had impaired behavioral performance in all tests. The largest impairment was noted in the tape test where the tape removal time from the left forelimb (contralateral to MCAO) was increased by approximately 10 fold (p<0.01). In contrast, rats subjected to TSD had complete recovery of sensorimotor performance consistent with a 2.5 fold smaller infarct volume and reduced morphological signs of neuronal injury at day 7 after MCAO. Our data suggest that brief TSD induces a neuroprotective response that limits the severity of a subsequent stroke, similar to rapid ischemic preconditioning.
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Affiliation(s)
- Mihai Moldovan
- Department of Physiology, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
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van der Weerd L, Lythgoe MF, Badin RA, Valentim LM, Akbar MT, de Belleroche JS, Latchman DS, Gadian DG. Neuroprotective effects of HSP70 overexpression after cerebral ischaemia--an MRI study. Exp Neurol 2005; 195:257-66. [PMID: 15936758 DOI: 10.1016/j.expneurol.2005.05.002] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2005] [Revised: 04/04/2005] [Accepted: 05/07/2005] [Indexed: 11/18/2022]
Abstract
Heat shock proteins (HSPs) have been reported to increase cell survival in response to a wide range of cellular challenges. However, the role of HSP70 overexpression is still a matter of debate, with some reports showing protection and others not. In order to resolve these discrepancies and further investigate the action of these proteins in vivo, transgenic mice overexpressing HSP70 have been compared to wild-type mice in a middle cerebral artery occlusion model of permanent cerebral ischaemia. Previously, the effect of HSP70 was assessed histologically postmortem. In this report, magnetic resonance imaging (MRI) was used to assess the mice in vivo after the onset of stroke. The lesion volume, as measured at 24 h using T(2)-weighted MRI, was significantly smaller in HSP70 transgenic mice compared with wild-type mice. The smaller lesion size in HSP70 transgenic mice could not be attributed to differences in vascular anatomy or in cerebral blood flow during occlusion. Additionally, the apparent diffusion coefficient showed different spatial and temporal patterns between the groups, suggesting that the damage within the lesion may be less severe for HSP70 transgenic mice. Thus, we conclude that overexpression of HSP70 reduces the overall lesion size and may also limit the tissue damage within the lesion.
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Affiliation(s)
- Louise van der Weerd
- RCS Unit of Biophysics, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UK.
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Gerriets T, Li F, Silva MD, Meng X, Brevard M, Sotak CH, Fisher M. The macrosphere model: evaluation of a new stroke model for permanent middle cerebral artery occlusion in rats. J Neurosci Methods 2003; 122:201-11. [PMID: 12573479 DOI: 10.1016/s0165-0270(02)00322-9] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
BACKGROUND AND PURPOSE The suture middle cerebral artery occlusion (MCAO) model is widely used for the simulation of focal cerebral ischemia in rats. This technique causes hypothalamic injury resulting in hyperthermia, which can worsen outcome and obscure neuroprotective effects. Herein, we introduce a new MCAO model that avoids these disadvantages. METHODS Permanent MCAO was performed by intraarterial embolization using six TiO(2) macrospheres (0.3-0.4 mm in diameter) or by the suture occlusion technique. Body temperature was monitored, functional and histologic outcome was assessed after 24 h. Additional 16 rats were subjected to macrosphere or suture MCAO. Lesion progression was evaluated using magnetic resonance imaging (MRI). RESULTS The animals subjected to suture MCAO developed hyperthermia (>39 degrees C), while the temperature remained normal in the macrosphere MCAO group. Infarct size, functional outcome and model failure rate were not significantly different between the groups. Lesion size on MRI increased within the first 90 min and remained unchanged thereafter in both groups. CONCLUSIONS The macrosphere MCAO model provides reproducible focal cerebral ischemia, similar to the established suture technique, but avoids hypothalamic damage and hyperthermia. This model, therefore, may be more appropriate for the preclinical evaluation of neuroprotective therapies and can also be used for stroke studies under difficult conditions, e.g., in awake animals or inside the MRI scanner.
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Affiliation(s)
- Tibo Gerriets
- Department of Neurology, University of Massachusetts Medical School, Worcester, MA 01655, USA.
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Campbell CA, Mackay KB, Patel S, King PD, Stretton JL, Hadingham SJ, Hamilton TC. Effects of isradipine, an L-type calcium channel blocker on permanent and transient focal cerebral ischemia in spontaneously hypertensive rats. Exp Neurol 1997; 148:45-50. [PMID: 9398449 DOI: 10.1006/exnr.1997.6611] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Permanent or transient focal cerebral ischemia was induced in spontaneously hypertensive rats (SHR) using the intraluminal filament method. Successful occlusion of the middle cerebral artery (MCA) was achieved using 4/O filaments (terminal diameter 0.20-0.25 mm) coated with poly-L-lysine. The L-type calcium channel blocker isradipine (2.5 mg/kg) administered subcutaneously 30 min following permanent MCA occlusion significantly reduced the volume of ischemic brain damage in the cerebral hemisphere (25%; P = 0.0001), cerebral cortex (18%; P = 0.0034), and caudate nucleus (33%; P = 0.0002) when assessed at 24 h post-MCA occlusion. Isradipine did not affect the functional deficit (measured using a subjective neurological scoring system) induced by MCA occlusion. In SHR undergoing transient (2 h) MCA occlusion isradipine administered 30 min post-MCA occlusion produced a significant reduction (47%; P = 0.001) in hemispheric infarct volume, whereas isradipine administered at the onset of reperfusion did not confer any significant neuroprotection. No change in functional deficit was seen with isradipine with either dosing paradigm at 24 h post-MCA occlusion. These results demonstrate that the intraluminal filament method of MCA occlusion can be used in the SHR strain and also substantiates the neuroprotective efficacy of isradipine in SHR models of permanent and transient focal cerebral ischemia.
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MESH Headings
- Animals
- Behavior, Animal
- Brain Damage, Chronic/etiology
- Brain Damage, Chronic/prevention & control
- Brain Edema/drug therapy
- Brain Edema/etiology
- Brain Edema/pathology
- Brain Ischemia/complications
- Brain Ischemia/drug therapy
- Brain Ischemia/metabolism
- Brain Ischemia/pathology
- Calcium Channel Blockers/administration & dosage
- Calcium Channel Blockers/pharmacology
- Calcium Channel Blockers/therapeutic use
- Calcium Channels/drug effects
- Calcium Channels, L-Type
- Drug Administration Schedule
- Drug Evaluation, Preclinical
- Ischemic Attack, Transient/complications
- Ischemic Attack, Transient/drug therapy
- Ischemic Attack, Transient/metabolism
- Ischemic Attack, Transient/pathology
- Isradipine/administration & dosage
- Isradipine/pharmacology
- Isradipine/therapeutic use
- Male
- Nerve Tissue Proteins/drug effects
- Neuroprotective Agents/administration & dosage
- Neuroprotective Agents/pharmacology
- Neuroprotective Agents/therapeutic use
- Rats
- Rats, Inbred SHR
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Affiliation(s)
- C A Campbell
- SmithKline Beecham Pharmaceuticals, Harlow, Essex, United Kingdom
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