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Fernández-Susavila H, Iglesias-Rey R, Dopico-López A, Pérez-Mato M, Sobrino T, Castillo J, Campos F. Inclusion criteria update for the rat intraluminal ischaemic model for preclinical studies. Dis Model Mech 2017; 10:1433-1438. [PMID: 29259024 PMCID: PMC5769604 DOI: 10.1242/dmm.029868] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 10/02/2017] [Indexed: 11/20/2022] Open
Abstract
Proper occlusion of the medial cerebral artery, as determined by laser Doppler monitoring, during cerebral ischaemia in rat models is an important inclusion criterion in experimental studies. However, successful occlusion of the artery does not always guarantee a reproducible infarct volume, which is crucial for validating the efficacy of new protective drugs. In a rat intraluminal ischaemic model, laser Doppler monitoring alone was compared with laser Doppler monitoring in combination with magnetic resonance angiography (MRA) and diffusion-weighted imaging (DWI). Twenty-eight animals showed successful occlusion and reperfusion determined with Doppler monitoring, with an infarct size at 24 h of 16.7±11.5% (determined as ischaemic damage with respect to the ipsilateral hemisphere volume). However, when arterial occlusion and infarct damage were analysed in these animals using MRA and DWI, respectively, 15 animals were excluded and only 13 animals were included, with an infarct size at 24 h of 21.6±6.1%, showing a variability in the infarct size significantly lower (P<0.05, F-test) than that obtained with Doppler monitoring alone. We also observed that blocking of the pterygopalatine artery (a maxillary artery that is usually occluded in the intraluminal ischaemic model) was not relevant for this model, at least in terms of infarct variability. These results show that laser Doppler monitoring is a necessary procedure, but not sufficient to guarantee a reproducible infarct volume, in a rat ischaemic model. Therefore, laser Doppler monitoring in combination with DWI and MRA represents a reliable inclusion protocol during ischaemic surgery for the analysis of new protective drugs. Summary: Laser Doppler monitoring in combination with diffusion-weighted imaging and magnetic resonance angiography represents a reliable inclusion protocol during ischaemic surgery for the analysis of protective drugs in the acute phase of stroke.
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Affiliation(s)
- Héctor Fernández-Susavila
- Clinical Neurosciences Research Laboratory, University Clinical Hospital of Santiago de Compostela, Health Research Institute of Santiago de Compostela (IDIS), 15706 Santiago de Compostela, Spain
| | - Ramón Iglesias-Rey
- Clinical Neurosciences Research Laboratory, University Clinical Hospital of Santiago de Compostela, Health Research Institute of Santiago de Compostela (IDIS), 15706 Santiago de Compostela, Spain
| | - Antonio Dopico-López
- Clinical Neurosciences Research Laboratory, University Clinical Hospital of Santiago de Compostela, Health Research Institute of Santiago de Compostela (IDIS), 15706 Santiago de Compostela, Spain
| | - María Pérez-Mato
- Clinical Neurosciences Research Laboratory, University Clinical Hospital of Santiago de Compostela, Health Research Institute of Santiago de Compostela (IDIS), 15706 Santiago de Compostela, Spain
| | - Tomás Sobrino
- Clinical Neurosciences Research Laboratory, University Clinical Hospital of Santiago de Compostela, Health Research Institute of Santiago de Compostela (IDIS), 15706 Santiago de Compostela, Spain
| | - José Castillo
- Clinical Neurosciences Research Laboratory, University Clinical Hospital of Santiago de Compostela, Health Research Institute of Santiago de Compostela (IDIS), 15706 Santiago de Compostela, Spain
| | - Francisco Campos
- Clinical Neurosciences Research Laboratory, University Clinical Hospital of Santiago de Compostela, Health Research Institute of Santiago de Compostela (IDIS), 15706 Santiago de Compostela, Spain
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Morris GP, Wright AL, Tan RP, Gladbach A, Ittner LM, Vissel B. A Comparative Study of Variables Influencing Ischemic Injury in the Longa and Koizumi Methods of Intraluminal Filament Middle Cerebral Artery Occlusion in Mice. PLoS One 2016; 11:e0148503. [PMID: 26870954 PMCID: PMC4752454 DOI: 10.1371/journal.pone.0148503] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2015] [Accepted: 01/19/2016] [Indexed: 12/19/2022] Open
Abstract
The intraluminal filament model of middle cerebral artery occlusion (MCAO) in mice and rats has been plagued by inconsistency, owing in part to the multitude of variables requiring control. In this study we investigated the impact of several major variables on survival rate, lesion volume, neurological scores, cerebral blood flow (CBF) and body weight including filament width, time after reperfusion, occlusion time and the choice of surgical method. Using the Koizumi method, we found ischemic injury can be detected as early as 30 min after reperfusion, to a degree that is not statistically different from 24 h post-perfusion, using 2,3,5-Triphenyltetrazolium chloride (TTC) staining. We also found a distinct increase in total lesion volume with increasing occlusion time, with 30–45 min a critical time for the development of large, reproducible lesions. Furthermore, although we found no significant difference in total lesion volume generated by the Koizumi and Longa methods of MCAO, nor were survival rates appreciably different between the two at 4 h after reperfusion, the Longa method produces significantly greater reperfusion. Finally, we found no statistical evidence to support the exclusion of data from animals experiencing a CBF reduction of <70% in the MCA territory following MCAO, using laser-Doppler flowmetry. Instead we suggest the main usefulness of laser-Doppler flowmetry is for guiding filament placement and the identification of subarachnoid haemorrhages and premature reperfusion. In summary, this study provides detailed evaluation of the Koizumi method of intraluminal filament MCAO in mice and a direct comparison to the Longa method.
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Affiliation(s)
- Gary P Morris
- Neurodegenerative Disorders, Garvan Institute of Medical Research, Sydney, Australia.,Faculty of Medicine, University of New South Wales, Sydney, Australia
| | - Amanda L Wright
- Neurodegenerative Disorders, Garvan Institute of Medical Research, Sydney, Australia
| | - Richard P Tan
- Neurodegenerative Disorders, Garvan Institute of Medical Research, Sydney, Australia.,Heart Research Institute, 2042 New South Wales, Sydney, Australia
| | - Amadeus Gladbach
- Dementia Research Unit, Department of Anatomy, School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, Australia
| | - Lars M Ittner
- Dementia Research Unit, Department of Anatomy, School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, Australia.,Neuroscience Research Australia, Sydney, Australia
| | - Bryce Vissel
- Neurodegenerative Disorders, Garvan Institute of Medical Research, Sydney, Australia.,Faculty of Medicine, University of New South Wales, Sydney, Australia.,Faculty of Science, University of Technology Sydney, Sydney, Australia
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Rifkind JM, Nagababu E, Barbiro-Michaely E, Ramasamy S, Pluta RM, Mayevsky A. Nitrite infusion increases cerebral blood flow and decreases mean arterial blood pressure in rats: a role for red cell NO. Nitric Oxide 2007; 16:448-56. [PMID: 17517526 DOI: 10.1016/j.niox.2007.04.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2006] [Revised: 03/14/2007] [Indexed: 11/26/2022]
Abstract
It has been proposed that the reduction of nitrite by red cells producing NO plays a role in the regulation of vascular tone. This hypothesis was investigated in rats by measuring the effect of nitrite infusion on mean arterial blood pressure (MAP), cerebral blood flow (CBF) and cerebrovascular resistance (CVR) in conjunction with the accumulation of red cell NO. The relative magnitude of the effects on MAP and CBF as well as the time dependent changes during nitrite infusion are used to distinguish between the effects on the peripheral circulation and the effects on the cerebral circulation undergoing cerebral autoregulation. The nitrite infusion was found to reverse the 96% increase in MAP and the 13% decrease in CBF produced by L-NAME inhibition of e-NOS. At the same time there was a 20-fold increase in oxygen stable red cell NO. Correlations of the red cell NO for individual rats support a role for red cell nitrite reduction in regulating vascular tone in both the peripheral and the cerebral circulation. Furthermore, data obtained prior to treatment is consistent with a contribution of red cell reduced nitrite in regulating vascular tone even under normal conditions.
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Affiliation(s)
- Joseph M Rifkind
- Molecular Dynamics Section, National Institute on Aging, 5600 Nathan Shock Drive, Baltimore, MD 21224, USA.
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Gedeborg R, Silander HC, Rubertsson S, Wiklund L. Cerebral ischaemia in experimental cardiopulmonary resuscitation--comparison of epinephrine and aortic occlusion. Resuscitation 2001; 50:319-29. [PMID: 11719162 DOI: 10.1016/s0300-9572(01)00350-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The apparent inability of epinephrine to improve outcome after cardiopulmonary resuscitation (CPR) could be caused by direct negative effects on the cerebral circulation. Constant aortic occlusion with a balloon catheter could be an alternative way to improve coronary and cerebral perfusion during CPR. The objective of the present study was to compare the effects of standard-dose epinephrine with balloon occlusion of the descending aorta on cortical cerebral blood flow augmentation during CPR. Ventricular fibrillation was induced in 24 anaesthetised piglets. A non-intervention interval of 9 min was followed by open-chest CPR. The animals were randomised to receive repeated intravenous bolus doses of epinephrine 20 microg/kg or balloon occlusion of the descending aorta. Focal cortical cerebral blood flow was measured continuously using laser-Doppler flowmetry. Balloon occlusion of the aorta resulted in a significantly higher mean cortical cerebral blood flow and a lower cerebral oxygen extraction ratio than epinephrine during CPR. After restoration of spontaneous circulation the cerebral perfusion appeared compromised to the same extent in both groups, with lower blood flow compared to baseline, high cerebral oxygen extraction and cerebral tissue acidosis. No difference in cerebral cortical vascular resistance between the two groups could be detected. It is concluded that aortic balloon occlusion was superior to epinephrine in cerebral blood flow augmentation during resuscitation and did not generate adverse effects on cerebral blood flow, oxygenation or tissue pH after restoration of spontaneous circulation. No evidence of cerebral vasoconstriction induced by standard-dose epinephrine was found.
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Affiliation(s)
- R Gedeborg
- Department of Anaesthesiology & Intensive Care, Uppsala University Hospital, S-751 85 Uppsala, Sweden.
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Abstract
Levels of endothelin-1 (ET-1), a potent endogenous vasoconstrictor, are elevated in plasma and cerebrospinal fluid (CSF) following cerebral ischemia and reperfusion injury. The present study sought insight into the potential differential vasoactive effects on the cerebral vasculature and resultant neural damage of ET-1 during normoxic vs. ischemic conditions and upon reperfusion. Under normoxic conditions, intrastriatal stereotaxic injection of exogenous ET-1 (40 pmol) induced a significant (P<0.05) reduction (</=29+/-12%) in the regional (striatal) cerebral blood flow measured by Laser Doppler flowmetry (CBF(LDF)) for up to 40 min in halothane-anesthetized male Long-Evans rats. Intrastriatal injection of ET-1 10 min after the onset of hypoxia (12% O(2), balance N(2)) tended to blunt, but not significantly, the striatal CBF(LDF) responses to the 35 min period of hypoxia. ET-1 given during reoxygenation significantly (P<0.05) reduced striatal CBF(LDF), which was similar to the effect of ET-1 during normoxia. ET-1-induced infarction when administered prior to hypoxia, but not during or post-hypoxia, was significantly (P<0.05) exacerbated compared to infarction of ET-1 without hypoxia. These results suggest that exogenous ET-1 administered into the brain parenchyma can induce an infarction associated with modulation of CBF(LDF) during the normoxic or reoxygenation period, but not during the hypoxic period and that the increased release of ET-1 in any pathological phase of cerebral ischemia contributes to irreversible neural damage with associated hemodynamic disturbances.
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Affiliation(s)
- L Park
- Department of Physiology and Saskatchewan Stroke Research Center, University of Saskatchewan, 107 Wiggins Road, Saskatoon, S7N 5E5, Saskatchewan, Canada.
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Gedeborg R, Silander HC, Ronne-Engström E, Rubertsson S, Wiklund L. Adverse effects of high-dose epinephrine on cerebral blood flow during experimental cardiopulmonary resuscitation. Crit Care Med 2000; 28:1423-30. [PMID: 10834690 DOI: 10.1097/00003246-200005000-00028] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
OBJECTIVE To study the effects of high-dose epinephrine, compared with standard-dose epinephrine, on the dynamics of superficial cortical cerebral blood flow as well as global cerebral oxygenation during experimental cardiopulmonary resuscitation. We hypothesized that high-dose epinephrine might be unable to improve cerebral blood flow during cardiopulmonary resuscitation as compared with standard-dose epinephrine. DESIGN Randomized controlled study. SETTING University hospital research laboratory. SUBJECTS A total of 20 male anesthetized piglets. INTERVENTIONS Ventricular fibrillation was induced. A nonintervention interval of 8 mins was followed by open-chest cardiopulmonary resuscitation. The animals were randomized to receive repeated bolus injections of either 20 microg/kg (standard-dose group, n = 10) or 200 microg/kg (high-dose group, n = 10) of epinephrine. MEASUREMENTS AND MAIN RESULTS Focal cortical cerebral blood flow was measured continuously by using laser Doppler flowmetry. The duration of blood flow increase was significantly shorter in the high-dose group after the second dose of epinephrine. In the high-dose group there was also a consistent tendency for lower peak levels and shorter duration of flow increase in response to repeated bolus doses of epinephrine. Cerebral oxygen extraction ratio was significantly lower in the high-dose group after administration of epinephrine. CONCLUSIONS Repeated bolus doses of epinephrine 200 microg/kg, as compared with 20 microg/kg, do not improve superficial cortical cerebral blood flow during experimental open-chest cardiopulmonary resuscitation. High-dose epinephrine appears to induce vasoconstriction of cortical cerebral blood vessels resulting in redistribution of blood flow from superficial cortex. This might be one explanation for the failure of high-dose epinephrine to improve overall outcome in clinical trials.
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Affiliation(s)
- R Gedeborg
- Department of Surgical Sciences, Anesthesiology & Intensive Care, Uppsala University Hospital, Sweden.
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Henshall DC, Butcher SP, Sharkey J. A rat model of endothelin-3-induced middle cerebral artery occlusion with controlled reperfusion. Brain Res 1999; 843:105-11. [PMID: 10528116 DOI: 10.1016/s0006-8993(99)01896-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Surge hyperemia and mechanical damage to the cerebrovascular endothelium may serve to exacerbate the neuropathological outcome in animal models of focal cerebral ischemia. We have modified an existing model of endothelin-1-induced middle cerebral artery (MCA) occlusion to enable controlled reperfusion without damage to the cerebral vasculature. Endothelin-1 (ET-1) and endothelin-3 (ET-3) were injected via a double-injection cannula into brain parenchyma adjacent to the MCA of anesthetized rats to produce focal cerebral ischemia. ET-1 and ET-3 produced large ischemic lesions that were restricted to those cortical and subcortical structures supplied by the MCA. The volume of ischemic damage produced by 100 pmol of ET-1 and ET-3 was similar. The endothelin-A (ET(A)) receptor antagonist FR139317 (3 or 30 nmol) injected 10 min after ET-1 did not significantly alter the volume of damage. By contrast, the lesion produced by ET-3 was completely inhibited by FR139317 at the 10 min time-point. FR139317 partially attenuated the ET-3-induced lesion when administered 30 min post-occlusion, but injection 90 min following ET-3 produced a lesion not different to that produced by ET-3 alone. These findings were supported by laser Doppler flowmetry which determined FR139317 induces reperfusion when injected 10 or 90 min following ET-3. ET-3-induced MCA occlusion is therefore amenable to reversal by the ET(A) receptor antagonist FR139317, and this model may offer a means to investigate the neuropathology of reperfusion without the procedure-related artifacts associated with some reperfusion models.
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Affiliation(s)
- D C Henshall
- Department of Pharmacology, University of Edinburgh, Edinburgh, UK.
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8
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Kirkeby OJ, Rise IR. Intracerebral laser Doppler blood flow measurements compared to blood flow in porcine internal carotid artery. J Clin Neurosci 1999. [DOI: 10.1016/s0967-5868(99)90033-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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9
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Forbes ML, Hendrich KS, Kochanek PM, Williams DS, Schiding JK, Wisniewski SR, Kelsey SF, DeKosky ST, Graham SH, Marion DW, Ho C. Assessment of cerebral blood flow and CO2 reactivity after controlled cortical impact by perfusion magnetic resonance imaging using arterial spin-labeling in rats. J Cereb Blood Flow Metab 1997; 17:865-74. [PMID: 9290584 DOI: 10.1097/00004647-199708000-00005] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We measured CBF and CO2 reactivity after traumatic brain injury (TBI) produced by controlled cortical impact (CCI) using magnetic resonance imaging (MRI) and spin-labeled carotid artery water protons as an endogenous tracer. Fourteen Sprague-Dawley rats divided into TBI (CCI; 4.02 +/- 0.14 m/s velocity; 2.5 mm deformation), sham, and control groups were studied 24 hours after TBI or surgery. Perfusion maps were generated during normocarbia (Paco2 30 to 40 mm Hg) and hypocarbia (PaCO2 15 to 25 mm Hg). During normocarbia, CBF was reduced within a cortical region of interest (ROI, injured versus contralateral) after TBI (200 +/- 82 versus 296 +/- 65 mL.100 g-1.min-1, P < 0.05). Within a contusion-enriched ROI, CBF was reduced after TBI (142 +/- 73 versus 280 +/- 64 mL.100 g-1.min-1, P < 0.05). Cerebral blood flow in the sham group was modestly reduced (212 +/- 112 versus 262 +/- 118 mL.100 g-1.min-1, P < 0.05). Also, TBI widened the distribution of CBF in injured and contralateral cortex. Hypocarbia reduced cortical CBF in control (48%), sham (45%), and TBI rats (48%) versus normocarbia, P < 0.05. In the contusion-enriched ROI, only controls showed a significant reduction in CBF, suggesting blunted CO2 reactivity in the sham and TBI group. CO2 reactivity was reduced in the sham (13%) and TBI (30%) groups within the cortical ROI (versus contralateral cortex). These values were increased twofold within the contusion-enriched ROI but were not statistically significant. After TBI, hypocarbia narrowed the CBF distribution in the injured cortex. We conclude that perfusion MRI using arterial spin-labeling is feasible for the serial, noninvasive measurement of CBF and CO2 reactivity in rats.
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Affiliation(s)
- M L Forbes
- Safar Center for Resuscitation Research, Pittsburgh, PA 15260, USA
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Soriano MA, Sanz O, Ferrer I, Planas AM. Cortical infarct volume is dependent on the ischemic reduction of perifocal cerebral blood flow in a three-vessel intraluminal MCA occlusion/reperfusion model in the rat. Brain Res 1997; 747:273-8. [PMID: 9046002 DOI: 10.1016/s0006-8993(96)01285-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Occlusion of the middle cerebral artery (MCA) causes a reduction of cerebral blood flow (CBF), which shows a progressive decrease from the periphery to the core of the MCA territory. The severity of ischemia is dependent on the duration of the ischemic episode and degree of CBF reduction. Fixing the ischemic episode to 1 h, we have examined whether or not cortical infarct size was related to the degree of CBF reduction in a perifocal cortical area in rats. One-hour intraluminal MCA occlusion accompanied with bilateral common carotid artery (CCA) occlusion (three-vessel occlusion/reperfusion model) was carried out in Sprague-Dawley rats and CBF was monitored with laser-Doppler flowmetry in the fronto-parietal cortex, an area which is perifocal to the core of the MCA territory. Finally, infarct size was measured 7 days later and was related to the corresponding CBF decrease. Sequential ipsilateral CCA, MCA and contralateral CCA occlusions produced reductions of CBF to 96%, 52% and 33% of baseline, respectively. Cortical infarct volume was found to be dependent on the corresponding reduction of perifocal cortical CBF during the ischemic episode. These results show that the reduction of CBF in the periphery of the MCA territory during 1-h focal ischemia determines infarct size in a three-vessel occlusion/reperfusion model.
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Affiliation(s)
- M A Soriano
- Departament de Farmacologia i Toxicologia, IIBB, CSIC, Barcelona, Spain
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