Disparity Between Low Cerebral Blood Flow and Clinical Signs of Cerebral Ischemia

Electroacupuncture (EA) is widely used to treat disorders of the nervous system, such as stroke. The aim of the present study was to investigate the effect of EA on cerebral blood flow (CBF) in cerebral ischemic rats. We developed an animal model of cerebral ischemia (CI) by occluding the blood flow of both common carotid arteries in Sprague-Dawley (SD) rats; 2 or 15 Hz EA was applied to both Zusanli acupoints. The levels of nitric oxide (NO) in the peripheral blood and amounts of calcitonin gene-related peptide (CGRP) in the cerebral cortex and thalamus were measured. In addition, L-N (G)-nitro arginine methyl ester (L-NAME) was used to measure the changes in CBF induced by EA in rats with and without CI. The results indicated that both 2 and 15 Hz EA increase the mean CBF in rats with and without CI. However, neither 2 nor 15 Hz EA induced changes in levels of NO in peripheral blood or changes in CGRP levels in cerebral cortex and thalamus. In addition, L-NAME did not change the increase in CBF. We concluded that both 2 and 15 Hz EA at both Zusanli acupoints induced the increase of CBF in rats with and without CI. Whether the effect of EA is related to NO or CGRP will be investigated in a future study.

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Cerebral blood flow and cerebral hematocrit in patients with cerebral ischemia measured by single-photon emission computed tomography

Acta Neurologica Scandinavica ◽

10.1111/j.1600-0404.1989.tb01805.x ◽

1989 ◽

Vol 80 ◽

pp. 9-13 ◽

Cited By ~ 8

Author(s):

Fumihiko Sakai ◽

Hisaka Igarashi ◽

Syuichi Suzuki ◽

Yoshiaki Tazaki

Keyword(s):

Computed Tomography ◽

Blood Flow ◽

Cerebral Blood Flow ◽

Cerebral Ischemia ◽

Single Photon ◽

Photon Emission ◽

Emission Computed Tomography ◽

Single Photon Emission ◽

Single Photon Emission Computed ◽

Photon Emission Computed Tomography

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Abstract 196: Sanguinate (PEGylated-carboxyhemoglobin-bovine) Improves Cerebral Blood Flow and Oxygen Extraction to Vulnerable Brain Regions in Patients at Risk for Delayed Cerebral Ischemia After Subarachnoid Hemorrhage

Stroke ◽

10.1161/str.48.suppl_1.196 ◽

2017 ◽

Vol 48 (suppl_1) ◽

Author(s):

Rajat Dhar ◽

Hemant Misra ◽

Michael Diringer

Keyword(s):

At Risk ◽

Blood Flow ◽

Cerebral Blood Flow ◽

Subarachnoid Hemorrhage ◽

Cerebral Ischemia ◽

Delayed Cerebral Ischemia ◽

Brain Regions ◽

Oxygen Extraction ◽

Patients At Risk ◽

Higher Doses

Introduction: Sanguinate is a dual-action oxygen transfer and carbon monoxide-releasing agent with efficacy in animal models of focal brain ischemia and established safety in health volunteers. We performed a dose-escalation study in subarachnoid hemorrhage (SAH) patients at risk for delayed cerebral ischemia (DCI) to evaluate tolerability and explore efficacy in improving cerebral blood flow (CBF) and flow-metabolism balance to vulnerable brain regions. Methods: 12 subjects were studied over three dose tiers: 160mg/kg, 240 mg/kg, and 320 mg/kg, with close safety evaluation prior to proceeding to higher doses. After baseline 15 O-PET measurement of global and regional CBF and oxygen extraction fraction (OEF), Sanguinate was infused over two hours; PET was repeated immediately after and again at 24-hours. Vulnerable brain regions were defined as those with baseline OEF ≥ 0.5. Results: Sanguinate infusion resulted in a significant but transient rise in mean arterial pressure (115±15 to 127±13 mm Hg) that was not dose-dependent. No adverse physiologic or clinical effects were observed with infusion at any dose. Global CBF did not rise significantly after Sanguinate (42.6±7 to 45.9±9 ml/100g/min, p=0.18). However, in the 28% of regions classified as vulnerable, Sanguinate resulted in a significant rise in CBF (42.2±11 to 51.2±18) and reduction in OEF (0.6±0.1 to 0.5±0.11, both p<0.001). The increase in regional CBF was only seen with the two higher doses but OEF improved in all tiers. However, response was attenuated at 24-hours. Conclusions: We safely administered a novel oxygen transport and vasodilating agent to a cohort of patients with SAH. Sanguinate infusion appeared to improve CBF and flow-metabolism balance in vulnerable brain regions and warrants further study in those at-risk for DCI. Higher or repeat dosing may be required for sustained efficacy.

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Cerebral Blood Flow and Metabolism and Cerebral Ischemia

Youmans Neurological Surgery ◽

10.1016/b978-1-4160-5316-3.00346-4 ◽

2011 ◽

pp. 3537-3562 ◽

Cited By ~ 2

Author(s):

Caroline C. Tan ◽

Vini G. Khurana ◽

Eduardo E. Benarroch ◽

Fredric B. Meyer

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Cerebral Ischemia

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Nefiracetam Improves the Impairment of Local Cerebral Blood Flow and Glucose Utilization after Chronic Focal Cerebral Ischemia in Rats

Pharmacology ◽

10.1159/000056160 ◽

2002 ◽

Vol 64 (3) ◽

pp. 119-125 ◽

Cited By ~ 6

Author(s):

Jingji Jin ◽

Shigeo Watabe ◽

Tsuneyuki Yamamoto

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Cerebral Ischemia ◽

Glucose Utilization ◽

Focal Cerebral Ischemia ◽

Local Cerebral Blood Flow

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The Angiotensin II Type 1—Receptor Blocker Candesartan Increases Cerebral Blood Flow, Reduces Infarct Size, and Improves Neurologic Outcome after Transient Cerebral Ischemia in Rats

Journal of Cerebral Blood Flow & Metabolism ◽

10.1097/00004647-200404000-00012 ◽

2004 ◽

Vol 24 (4) ◽

pp. 467-474 ◽

Cited By ~ 86

Author(s):

Tobias Engelhorn ◽

Sophia Goerike ◽

Arnd Doerfler ◽

Christine Okorn ◽

Michael Forsting ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Angiotensin Ii ◽

Cerebral Ischemia ◽

Infarct Size ◽

Laser Doppler Flowmetry ◽

Transient Cerebral Ischemia ◽

Doppler Flowmetry ◽

Treatment Regimens

The goal of the present study was to test the impact of administration time of the angiotensin II type 1–receptor blocker candesartan on cerebral blood flow (CBF), infarct size, and neuroscore in transient cerebral ischemia. Therefore, 1-hour middle cerebral artery occlusion (MCAO) was followed by reperfusion. Rats received 0.5-mg/kg candesartan intravenously 2 hours before MCAO (pretreatment), 24 hours after MCAO, every 24 hours after MCAO, or 2 hours before and every 24 hours after MCAO. Infarct size (mm3) and a neuroscore at day 7 were compared with controls. CBF was quantified by radiolabeled microspheres and laser-Doppler flowmetry. Compared with controls (95 ± 8), infarct size in candesartan-treated groups was smaller (59 ± 5, 68 ± 10, 28 ± 3, and 15 ± 3, respectively; P < 0.05). Although there was no difference in neuroscore between pretreatment and controls (1.55 ± 0.18, 1.80 ± 0.13), other treatment regimens resulted in improved neuroscores (1.33 ± 0.16, 1.11 ± 0.11, 0.73 ± 0.15; P < 0.05). CBF in pretreated animals at 0.5 hours after MCAO was significantly higher than in controls (0.58 ± 0.09 mL · g−1 ·· min−1 and 44% ± 7% of baseline compared with 0.49 ± 0.06 mL · g−1 ·· min−1 and 37% ± 6%, microspheres and laser-Doppler flowmetry; P < 0.05). Thus, candesartan reduces infarct size even if administered only during reperfusion. Apart from pretreatment, other treatment regimens result in significantly improved neuroscores. In the acute phase of cerebral ischemia, candesartan increases CBF.

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