Greatly improved survival and neuroprotection in aquaporin‐4‐knockout mice following global cerebral ischemia

Background Permissive hypercapnia is a widely practiced protective ventilatory strategy that has significant protective effects on several models of in vitro and in vivo neuronal injury. However, conclusive effects of permissive hypercapnia on cerebral ischemia are still unknown. Methods One hundred sixty male Wistar rats were divided into five groups: S group (control), ischemia-reperfusion (I/R) group, P1 group, P2 group, and P3 group. I/R was induced by bilateral occlusion of the common carotid arteries, combined with controlled hypotension for 15 min. In groups P1, P2, and P3, the rats inhaled carbon dioxide for 2 h during reperfusion to keep Paco2 within the ranges of 60-80 mmHg, 80-100 mmHg, and 100-120 mmHg, respectively. After 24 and 72 h, neurologic deficit scores, ultrastructural changes, apoptotic neurons, and brain wet-to-dry weight ratios were observed. Caspase-3 and aquaporin-4 protein expression and caspase-3 activity were analyzed. Results Compared with groups I/R and P3, groups P1 and P2 had better neurologic deficit scores and fewer ultrastructural histopathologic changes. I/R-induced cerebral apoptosis was also significantly reduced. The neuroprotective effect was significantly increased in the P2 group compared with the P1 group. There was a significant increase of brain water content and of aquaporin-4 levels in the P3 group. Conclusions Mild to moderate hypercapnia (Paco2 60-100 mmHg) is neuroprotective after transient global cerebral I/R injury. Such a protection might be associated with apoptosis-regulating proteins. In contrast, severe hypercapnia (Paco2 100-120 mmHg) increased brain injury, which may be caused by increased brain edema.

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Ultrastorcture of Cerebellar Purkinje Cells in Rats Subjected To Partial Global Cerebral Ischemia

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100120060 ◽

1985 ◽

Vol 43 ◽

pp. 674-675

Author(s):

R.V.W. Dimlich ◽

M.H. Biros

Keyword(s):

Cerebral Ischemia ◽

Purkinje Cells ◽

Cell Types ◽

Microscopic Level ◽

Global Cerebral Ischemia ◽

Light Microscopic Level ◽

Cerebellar Damage ◽

Cerebellar Injury ◽

Cerebellar Purkinje Cells ◽

Cell Changes

In severe cerebral ischemia, Purkinje cells of the cerebellum are one of the cell types most vulnerable to anoxic damage. In the partial (forebrain) global ischemic (PGI) model of the rat, Paljärvi noted at the light microscopic level that cerebellar damage is inconsistant and when present, milder than in the telencephalon, diencephalon and rostral brain stem. Cerebellar injury was observed in 3 of 4 PGI rats following 5 minutes of reperfusion but in none of the rats after 90 min of reperfusion. To evaluate a time between these two extremes (5 and 90 min), the present investigation used the PGI model to study the effects of ischemia on the ultrastructure of cerebellar Purkinje cells in rats that were sacrificed after 30 min of reperfusion. This time also was chosen because lactic acid that is thought to contribute to ischemic cell changes in PGI is at a maximum after 30 min of reperfusion.

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Short moderate post-ischemia physical activity improve cognition and modified glutamate change in hippocampus after global cerebral ischemia

Advances in Sport Science and Computer Science ◽

10.2495/cccs131011 ◽

2014 ◽

Author(s):

Jue Wang ◽

Yuhan Wang ◽

Taiming Zhang ◽

Hao Wu ◽

Kun Liu

Keyword(s):

Physical Activity ◽

Cerebral Ischemia ◽

Global Cerebral Ischemia

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Effect of carvedilol on the redox-status of plasma low-molecular-weight aminothyols in rats with acute cerebral ischemia

ZHurnal «Patologicheskaia fiziologiia i eksperimental`naia terapiia» ◽

10.25557/0031-2991.2018.03.12-18 ◽

2018 ◽

pp. 12-18

Author(s):

К.А. Никифорова ◽

В.В. Александрин ◽

П.О. Булгакова ◽

А.В. Иванов ◽

Э.Д. Вирюс ◽

...

Keyword(s):

Molecular Weight ◽

Cerebral Ischemia ◽

Carotid Arteries ◽

Redox Status ◽

Global Cerebral Ischemia ◽

Low Molecular Weight ◽

Adrenergic Antagonist ◽

Acute Cerebral Ischemia ◽

Common Carotid Arteries ◽

Reduced Forms

Цель. Установить влияние неспецифического адреноблокатора карведилола на редокс-статус низкомолекулярных аминотиолов (цистеин, гомоцистеин, глутатион) в плазме крови при моделировании глобальной ишемии головного мозга у крыс. Методика. Нами была использована модель глобальной ишемии (пережатие общих сонных артерий с геморрагией длительностью 15 мин). Препарат вводили за 1 ч до операции. Уровни аминотиолов измеряли через 40 мин после начала реперфузии. Анализ уровня аминотиолов проводили методом жидкостной хроматографии. Результаты. Установлено, что у крыс, не подвергавшихся ишемии, карведилол в дозе 10 мг/кг вызывает рост редокс-статуса цистеина и глутатиона (в 3 и 3,5 раза соответственно по сравнению с контролем, p = 0,04 и p = 0,008) за счет увеличения их восстановленных форм. При ишемии данного эффекта не наблюдалось. Редокс-статус у крыс с ишемией на фоне карведилола (Цис = 0,85 ± 0,14%, Глн = 1,8 ± 0,7%, Гцис = 1,1 ± 0,8%) оставался таким же низким, как и у крыс с ишемией без введения карведилола (р > 0,8). Заключение. Полученный результат демонстрирует, что в условиях ишемии головного мозга карведилол не оказывает эффекта на гомеостаз аминотиолов плазмы крови, несмотря на выраженный антиоксидантный эффект в нормальных условиях. Aim. Effect of a nonspecific adrenergic antagonist carvedilol on the redox status of plasma low-molecular-weight aminothiols (cysteine, homocysteine, glutathione) was studied in rats with global cerebral ischemia (occlusion of common carotid arteries with hemorrhage). Methods. A model of global ischemia (occlusion of common carotid arteries with 15-min hemorrhage) was used. The drugs were administered one hour before the operation. Aminothiol levels were measured by HPLC with UV detection at 40 minutes after the onset of reperfusion. Results. Carvedilol 10 mg/kg increased the redox status of cysteine and glutathione in rats not exposed to ischemia (3 and 3.5 times, respectively, compared with the control, p = 0.04 and p = 0.008, respectively) but not of homocysteine, by increasing their reduced forms. However, this effect was not observed in ischemia. In rats with ischemia treated with carvedilol, the redox status (Cys = 0.85 ± 0.14%, GSH = 1.8 ± 0.7%, Hcys = 1.1 ± 0.8%) remained low similar to that in rats with ischemia not treated with carvedilol (p >0.8, 0.8, and 0.9, respectively). Conclusion. Carvedilol did not affect the homeostasis of blood plasma thiols in cerebral ischemia despite the pronounced antioxidant effect under the normal conditions.

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Faculty Opinions recommendation of Increased brain injury and worsened neurological outcome in interleukin-4 knockout mice after transient focal cerebral ischemia.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.12024957.13163055 ◽

2011 ◽

Author(s):

Johannes Boltze

Keyword(s):

Brain Injury ◽

Cerebral Ischemia ◽

Knockout Mice ◽

Neurological Outcome ◽

Focal Cerebral Ischemia ◽

Interleukin 4 ◽

Transient Focal Cerebral Ischemia

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Exploring the Role of Remote Ischemic Preconditioning In Long Term Cognitive Impairment after Global Ischemia-Reperfusion-Induced Vascular Dementia in Mice

Journal of Clinical and Medical Research ◽

10.37191/mapsci-2582-4333-2(5)-045 ◽

2020 ◽

Author(s):

Amteshwar Singh Jaggi

Keyword(s):

Cognitive Impairment ◽

Cerebral Ischemia ◽

Vascular Dementia ◽

Ischemic Preconditioning ◽

Ischemia Reperfusion ◽

Remote Ischemic Preconditioning ◽

Global Cerebral Ischemia ◽

Cerebral Ischemic ◽

The Brain

Aim: The aim of the present study is to explore the neuroprotective effects of remote ischemic preconditioning in long term cognitive impairment after global cerebral ischemia induced-vascular dementia in mice. Material and methods: The mice were subjected to global cerebral ischemia by occluding the bilateral common carotid arteries for 12 minutes followed by the 24 hours of the reperfusion. The remote ischemic preconditioning stimulus was delivered in the form of 4 cycles of ischemia/reperfusion for 5 minutes each. The cerebral ischemic injury induced-long term cognitive impairment-related learning and memory alterations was assessed using morris water maze, the motor performances of the animals were evaluated using rota-rod test and neurological severity score. The cerebral infract size of the brain were quantified using triphenyltetrazolium chloride staining. Results: Global cerebral ischemia causes long term memory impairment, decreases motor performances and increases the brain infract size in animals. The delivery of remote ischemic preconditioning stimulus significantly abolished the long-term cognitive impairment and ameliorates the motor performances as well as cerebral infract size in brain. Conclusion: The remote ischemic preconditioning mediates neuro protection against global cerebral ischemic injury induced long-term cognitive impairment.

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