scholarly journals Quantitation of Photochemically Induced Focal Cerebral Ischemia in the Rat

1988 ◽  
Vol 8 (1) ◽  
pp. 89-95 ◽  
Author(s):  
John J. Grome ◽  
Gerlinde Gojowczyk ◽  
Wolfgang Hofmann ◽  
David I. Graham
Keyword(s):  
Cerebral Ischemia ◽  
Water Content ◽  
Rose Bengal ◽  
Tissue Damage ◽  
Focal Cerebral Ischemia ◽  
Ischemic Damage ◽  
Brain Water Content ◽  
Ischemic Insult ◽  
Ischemic Lesion ◽  
Brain Water

This study was carried out with a recently developed model of focal cerebral ischemia in the rat based on the photochemical induction of thrombotic stroke using the dye Rose Bengal. We examined the change in the volume of the lesion and brain water content, in separate groups of rats, at different times (1, 4, 24, 72, and 168 h) after the induction of the ischemic lesion. The volume of ischemic damage increased rapidly between 1 and 24 h after the ischemic insult and decreased between 24 and 168 h. The lesion at 168 h was significantly larger than that following 1 h of ischemia and similar to that obtained at 4 h, suggesting that the maximum extent of tissue damage (without the involvement of significant edema) was reached within the first 4 h in this model. The enlargement of the lesion after 4 h correlated closely with changes in brain water content.

scholarly journals Neuroprotection of Sanhua Decoction against Focal Cerebral Ischemia/Reperfusion Injury in Rats through a Mechanism Targeting Aquaporin 4

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Lin Lu ◽  
Hui-qin Li ◽  
Ji-huang Li ◽  
Ai-ju Liu ◽  
Guo-qing Zheng
Keyword(s):  
Cerebral Ischemia ◽  
Water Content ◽  
Brain Edema ◽  
Focal Cerebral Ischemia ◽  
Ischemia Reperfusion ◽  
Aquaporin 4 ◽  
Brain Water Content ◽  
Aqp4 Expression ◽  
Cerebral Ischemia Reperfusion ◽  
Brain Water

Sanhua decoction (SHD) is a famous classic Chinese herbal prescription for ischemic stroke, and aquaporin 4 (AQP4) is reported to play a key role in ischemic brain edema. This study aimed to investigate neuroprotection of SHD against focal cerebral ischemia/reperfusion (I/R) injury in rats and explore the hypothesis that AQP4 probably is the target of SHD neuroprotection against I/R rats. Lentiviral-mediated AQP4-siRNA was inducted into adult male Sprague-Dawley rats via intracerebroventricular injection. The focal cerebral ischemia/reperfusion model was established by occluding middle cerebral artery. Neurological examinations were performed according to Longa Scale. Brain water content, was determined by wet and dry weight measurement. Western blot was adopted to test the AQP4 expression in ipsilateral hippocampus. After the treatment, SHD alleviated neurological deficits, reduced brain water content and downregulated the expression of AQP4 at different time points following I/R injury. Furthermore, neurobehavioral function and brain edema after I/R were significantly attenuated via downregulation of AQP4 expression when combined with AQP4-siRNA technology. In conclusion, SHD exerted neuroprotection against focal cerebral I/R injury in rats mainly through a mechanism targeting AQP4.

scholarly journals Electroacupuncture Attenuates Cerebral Ischemia and Reperfusion Injury in Middle Cerebral Artery Occlusion of Rat via Modulation of Apoptosis, Inflammation, Oxidative Stress, and Excitotoxicity

2016 ◽  
Vol 2016 ◽  
pp. 1-15 ◽  
Author(s):  
Mei-hong Shen ◽  
Chun-bing Zhang ◽  
Jia-hui Zhang ◽  
Peng-fei Li
Keyword(s):  
Cerebral Ischemia ◽  
Middle Cerebral Artery ◽  
Water Content ◽  
Middle Cerebral Artery Occlusion ◽  
Cerebral Artery ◽  
Artery Occlusion ◽  
Antioxidant Systems ◽  
Brain Water Content ◽  
Cerebral Artery Occlusion ◽  
Brain Water

Electroacupuncture (EA) has several properties such as antioxidant, antiapoptosis, and anti-inflammatory properties. The current study was to investigate the effects of EA on the prevention and treatment of cerebral ischemia-reperfusion (I/R) injury and to elucidate possible molecular mechanisms. Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) for 2 h followed by reperfusion for 24 h. EA stimulation was applied to bothBaihuiandDazhuiacupoints for 30 min in each rat per day for 5 successive days before MCAO (pretreatment) or when the reperfusion was initiated (treatment). Neurologic deficit scores, infarction volumes, brain water content, and neuronal apoptosis were evaluated. The expressions of related inflammatory cytokines, apoptotic molecules, antioxidant systems, and excitotoxic receptors in the brain were also investigated. Results showed that both EA pretreatment and treatment significantly reduced infarct volumes, decreased brain water content, and alleviated neuronal injury in MCAO rats. Notably, EA exerts neuroprotection against I/R injury through improving neurological function, attenuating the inflammation cytokines, upregulating antioxidant systems, and reducing the excitotoxicity. This study provides a better understanding of the molecular mechanism underlying the traditional use of EA.

scholarly journals Diffusion-Weighted Magnetic Resonance Imaging of Acute Focal Cerebral Ischemia: Comparison of Signal Intensity with Changes in Brain Water and Na+,K+ -ATPase Activity

1994 ◽  
Vol 14 (2) ◽  
pp. 332-336 ◽  
Author(s):  
Jan Mintorovitch ◽  
G. Y. Yang ◽  
Hiroaki Shimizu ◽  
John Kucharczyk ◽  
Pak H. Chan ◽  
...  
Keyword(s):  
Cerebral Ischemia ◽  
Magnetic Resonance ◽  
Atpase Activity ◽  
Water Content ◽  
Signal Intensity ◽  
Focal Cerebral Ischemia ◽  
Mr Images ◽  
Diffusion Weighted ◽  
Acute Cerebral Ischemia ◽  
Brain Water

Diffusion-weighted magnetic resonance (MR) images from rats during acute cerebral ischemia induced by middle cerebral artery occlusion were analyzed for correspondence with changes in brain water, cation concentrations, and Na+,K+-ATPase activity measured in vitro after 30 or 60 min of ischemia. In the ischemic hemisphere, signal intensity was increased at 30 min (p < 0.05 vs contralateral hemisphere) and further increased at 60 min. Na+,K+-ATPase activity was 34% lower in ischemic cortex and 40% lower in ischemic basal ganglia after 30 min (p < 0.05), but water content and Na+ and K+ concentrations were not significantly different between hemispheres. After 60 min, water content and Na+ concentration were increased, and both Na+,K+-ATPase activity and K+ concentration were decreased in the ischemic hemisphere (p < 0.05). These findings are consistent with the hypothesis that the early onset of signal hyperintensity in diffusion-weighted MR images may reflect cellular edema associated with impaired membrane pump function. Early in vivo detection and localization of potentially reversible ischemic cerebral edema may have important research and clinical applications.

Effects of Neopterin on Focal Cerebral Ischemia In Rats

Pteridines ◽  
1996 ◽  
Vol 7 (4) ◽  
pp. 157-159
Author(s):  
Toshiyuki Arai ◽  
Hisanari Ishii ◽  
Hiroko Mori ◽  
Kenjiro Mori ◽  
Shuji Kojima
Keyword(s):  
Magnetic Resonance Imaging ◽  
Cerebral Ischemia ◽  
Neuronal Damage ◽  
Focal Cerebral Ischemia ◽  
Treated Group ◽  
Ischemic Damage ◽  
Resonance Imaging ◽  
Ischemic Lesion ◽  
Glial Reaction ◽  
Magnetic Resonance Imaging Mri

Summary We examined the effects of neopterin on focal cerebral ischemia induced by transient (2 h) occlusion of the middle cerebral artery (MCA) in rats. Neopterin was administered 10 min before reperfusion (3 mg/kg i.p). The ischemic damage was evaluated one week after the MCA occlusion by magnetic resonance imaging (MRI) and by the immunohistochemical reaction for microtubule-associated protein 2 (MAP2). The ischemic lesion detected by MRI was significantly smaller in the neopterin-treated group than in the non-treated group (n=4 in each group, p<0.05). However, the ischemic neuronal damage determined by MAP2 in the neopterintreated group was not significantly different from that in the non-treated group. Since MRI is thought to reflect the distribution of not only neurons but also glial cells, these results may indicate the effects of neopterin on the glial reaction in focal cerebral ischemia.

scholarly journals Tea Polysaccharide (TPS) Reduces Astrocytes Apoptosis Induced by Oxygen-Glucose Deprivation/Reoxygenation by Regulating the miR-375/SRXN1 Axis

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Ying Jiang ◽  
Hongmei Sun ◽  
Zhiqi Yin ◽  
Jun Yan
Keyword(s):  
Cerebral Ischemia ◽  
Cell Viability ◽  
Water Content ◽  
Caspase 3 ◽  
Ischemia Reperfusion ◽  
Glucose Deprivation ◽  
Oxygen Glucose Deprivation ◽  
Brain Water Content ◽  
Cerebral Ischemia Reperfusion ◽  
Brain Water

Objective. To investigate the effect of tea polysaccharides (TPS) mediated by miR-375/SRXN1 axis on mice with cerebral ischemia-reperfusion injury and proliferation and apoptosis of astrocytes (AS) conducted with oxygen-glucose deprivation/reoxygenation (OGD/R). Methods. Mouse model of middle cerebral artery occlusion (MCAO) and OGD/R-induced AS injury model were established; brain obstruction volume was measured by TTC staining; dry/wet weight ratio was used for measuring brain water content; hydrogen peroxide (H2O2) content in brain tissue was measured by H2O2 assay kit; cell viability and apoptosis rate were detected by MTT assay and flow cytometry, respectively; the expression level of miR-375 in OGD/R-AS was detected using qPCR; dual-luciferase reporter assay was used to verify the targeting relationship between miR-375 and SRXN1; mRNA levels of miR-375, SRXN1, Bcl-2, Bax, and caspase-3 were measured by qPCR; the protein levels of SRXN1, Bcl-2, Bax, and caspase-3 were measured by Western blotting. Results. The volume of cerebral obstruction, brain water content and H2O2 content in mice decreased gradually with the increase of TPS concentration. TPS treatment in vitro could effectively improve OGD/R-AS viability and reduce the apoptotic rate; overexpression of miR-375 inhibited AS viability but increased the apoptotic rate; TPS treatment resulted in a decrease in the expression of miR-375 in OGD/R-AS; MiR-375 targeted SRXN1 in AS; inhibition of miR-375 expression significantly upregulated SRXN1 levels; TPS treatment with simultaneous overexpression of SRXN1 significantly increased OGD/R-AS activity and reduced apoptosis; however, TPS treatment with simultaneous overexpression of SRXN1 and miR-375 resulted in no significant difference in cell viability and apoptosis rate compared with the control group. Conclusion. TPS reduces astrocyte injury induced by cerebral ischemia-reperfusion in mice by regulating the miR-375/SRXN1 molecular axis.

Aggravation of infarct formation by brain swelling in a large territorial stroke: a target for neuroprotection?

2008 ◽  
Vol 109 (2) ◽  
pp. 287-293 ◽  
Author(s):  
Maureen Walberer ◽  
Nouha Ritschel ◽  
Max Nedelmann ◽  
Kai Volk ◽  
Clemens Mueller ◽  
...  
Keyword(s):  
Water Content ◽  
Sham Operation ◽  
Lesion Volume ◽  
Brain Water Content ◽  
Brain Swelling ◽  
Lesion Formation ◽  
Ischemic Lesion ◽  
Cerebral Herniation ◽  
The Impact ◽  
Brain Water

Object In territorial stroke vasogenic edema formation leads to elevated intracranial pressure (ICP) and can cause herniation and death. Brain swelling further impairs collateral blood flow to the ischemic penumbra and causes mechanical damage to adjacent brain structures. In the present study the authors sought to quantify the impact of this space-occupying effect on ischemic lesion formation. Methods Wistar rats were assigned to undergo bilateral craniectomy or a sham operation and then were subjected to temporary middle cerebral artery occlusion (MCAO) for 90 minutes. A clinical evaluation and 7-T MR imaging studies were performed 5 and 24 hours after MCAO. The absolute brain water content was determined at 24 hours by using the wet/dry method. Results Bilateral craniectomy before MCAO led to a drastic reduction in lesion volume at both imaging time points (p < 0.0001). Ischemic lesion volume was 2.7- and 2.3-fold larger in sham-operated animals after 5 and 24 hours, respectively. Clinical scores were likewise better in rats that had undergone craniectomy (p < 0.05). After 24 hours the midline shift differed significantly between the 2 groups (p < 0.001), but not after 5 hours. The relation between brain water content and ischemic lesion volume as well as the T2 relaxation time within the infarcted area was not different between the groups (p > 0.05). Conclusions The data indicated that collateral damage caused by the space-occupying effect of a large MCA territory stroke contributes seriously to ischemic lesion formation. The elimination of increased ICP thus must be regarded as a highly neuroprotective measure, rather than only a life-saving procedure to prevent cerebral herniation. Further clinical trials should reveal the neuroprotective potential of surgical and pharmacological ICP-lowering therapeutic approaches.

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