scholarly journals Catechin prevents severe dyslipidemia-associated changes in wall biomechanics of cerebral arteries in LDLr−/−:hApoB+/+ mice and improves cerebral blood flow

2012 ◽  
Vol 302 (6) ◽  
pp. H1330-H1339 ◽  
Author(s):  
Virginie Bolduc ◽  
Edward Baraghis ◽  
Natacha Duquette ◽  
Nathalie Thorin-Trescases ◽  
Jean Lambert ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Endothelial Dysfunction ◽  
Cerebral Artery ◽  
Cerebral Arteries ◽  
Strain Curve ◽  
Cerebral Hypoperfusion ◽  
Wall Structure ◽  
Artery Wall

Endothelial dysfunction and oxidative stress contribute to the atherosclerotic process that includes stiffening of large peripheral arteries. In contrast, our laboratory previously reported a paradoxical increase in cerebrovascular compliance in LDLr−/−:hApoB+/+ atherosclerotic (ATX) mice ( 7 ). We hypothesized that prevention of cerebral artery endothelial dysfunction with a chronic dietary antioxidant intake would normalize the changes in cerebral artery wall structure and biomechanics and prevent the decline in basal cerebral blood flow associated with atherosclerosis. Three-month-old ATX mice were treated, or not, for 3 mo with the polyphenol (+)-catechin (CAT; 30 mg·kg−1·day−1) and compared with wild-type controls. In isolated, pressurized cerebral arteries from ATX mice, CAT prevented endothelial dysfunction (deterioration of endothelium-dependent, flow-mediated dilations; P < 0.05), the inward hypertrophic structural remodeling (increase in the wall-to-lumen ratio; P < 0.05), and the rise in cerebrovascular compliance (rightward shift of the stress-strain curve measured in passive conditions, reflecting mechanical properties of the arterial wall; P < 0.05). Doppler optical coherence tomography imaging in vivo confirmed these findings, showing that cerebral compliance was higher in ATX mice and normalized by CAT ( P < 0.05). CAT also prevented basal cerebral hypoperfusion in ATX mice ( P < 0.05). Active remodeling of the cerebrovascular wall in ATX mice was further suggested by the increase ( P < 0.05) in pro-metalloproteinase-9 activity, which was normalized by CAT. We conclude that, by preserving the endothelial function, a chronic treatment with CAT prevents the deleterious effect of severe dyslipidemia on cerebral artery wall structure and biomechanical properties, contributing to preserving resting cerebral blood flow.

scholarly journals Amylin: Localization, Effects on Cerebral Arteries and on Local Cerebral Blood Flow in the Cat

2001 ◽  
Vol 1 ◽  
pp. 168-180 ◽  
Author(s):  
Lars Edvinsson ◽  
Peter J. Goadsby ◽  
Rolf Uddman
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Blood Vessels ◽  
Cerebral Arteries ◽  
In Vivo Studies ◽  
Cerebral Blood Vessels ◽  
Local Cerebral Blood Flow ◽  
Doppler Flowmetry

Amylin and adrenomedullin are two peptides structurally related to calcitonin gene-related peptide (CGRP). We studied the occurrence of amylin in trigeminal ganglia and cerebral blood vessels of the cat with immunocytochemistry and evaluated the role of amylin and adrenomedullin in the cerebral circulation by in vitro and in vivo pharmacology. Immunocytochemistry revealed that numerous nerve cell bodies in the trigeminal ganglion contained CGRP immunoreactivity (-ir); some of these also expressed amylin-ir but none adrenomedullin-ir. There were numerous nerve fibres surrounding cerebral blood vessels that contained CGRP-ir. Occasional fibres contained amylin-ir while we observed no adrenomedullin-ir in the vessel walls. With RT-PCR and Real-Time�PCR we revealed the presence of mRNA for calcitonin receptor-like receptor (CLRL) and receptor-activity-modifying proteins (RAMPs) in cat cerebral arteries. In vitro studies revealed that amylin, adrenomedullin, and CGRP relaxed ring segments of the cat middle cerebral artery. CGRP and amylin caused concentration-dependent relaxations at low concentrations of PGF2a-precontracted segment (with or without endothelium) whereas only at high concentration did adrenomedullin cause relaxation. CGRP8-37 blocked the CGRP and amylin induced relaxations in a parallel fashion. In vivo studies of amylin, adrenomedullin, and CGRP showed a brisk reproducible increase in local cerebral blood flow as examined using laser Doppler flowmetry applied to the cerebral cortex of the a-chloralose�anesthetized cat. The responses to amylin and CGRP were blocked by CGRP8-37. The studies suggest that there is a functional sub-set of amylin-containing trigeminal neurons which probably act via CGRP receptors.

Selected Contribution: Effects of aging on cerebrovascular tone and [Ca2+]i

2003 ◽  
Vol 95 (4) ◽  
pp. 1746-1754 ◽  
Author(s):  
Greg G. Geary ◽  
John N. Buchholz
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Cerebral Artery ◽  
Cerebral Arteries ◽  
No Synthase ◽  
The Other ◽  
Intraluminal Pressure ◽  
Age Dependent ◽  
Old Rats ◽  
Cerebral Blood Flow Autoregulation

The lower limits of cerebral blood flow autoregulation shift toward high pressures in aged compared with young rats. Intraluminal pressure stimulates contractile mechanisms in cerebral arteries that might, in part, cause an age-dependent shift in autoregulation. The present project tested two hypotheses. First, cerebral artery tone is greater in isolated arteries from aged compared with mature adult rats. Second, aging decreases the modulatory effect of endothelium-derived nitric oxide (NO) and increases vascular smooth muscle Ca2+ sensitivity. Isolated segments of middle cerebral arteries from male 6-, 12-, 20-, and 24-mo-old Fischer 344 rats were cannulated and loaded with fura-2. Diameter and Ca2+ responses to increasing pressure were measured in HEPES, during NO synthase inhibition [ NG-nitro-l-arginine methyl ester (l-NAME)], and after removal of the endothelium. Cerebral artery tone (with endothelium) increased with age. Only at the lowest pressure (20 and 40 mmHg) was intracellular Ca2+ concentration ([Ca2+]i) greater in arteries from 24-mo-old rats compared with the other age groups. l-NAME-sensitive constriction increased significantly in arteries from 6- to 20-mo-old rats but declined significantly thereafter in arteries from 24-mo-old rats. [Ca2+]i was less in arteries from 24-mo-old rats compared with the other groups after treatment with l-NAME. Another endothelial-derived factor, insensitive to l-NAME, also decreased significantly with age. For example, at 60 mmHg, the l-NAME-insensitive constriction decreased from 47 ± 10, 42 ± 5, 21 ± 2, and 3 ± 1 μm in 6-, 12-, 20-, and 24-mo-old rats, respectively. Our data suggest that aging alters cerebral artery tone and [Ca2+]i responses through endothelial-derived NO synthase-sensitive and -insensitive mechanisms. The combined effect of greater cerebral artery tone with less endothelium-dependent modulation may in part contribute to the age-dependent shift in cerebral blood flow autoregulation.

scholarly journals Blood Flow Distribution in Cerebral Arteries

2015 ◽  
Vol 35 (4) ◽  
pp. 648-654 ◽  
Author(s):  
Laleh Zarrinkoob ◽  
Khalid Ambarki ◽  
Anders Wåhlin ◽  
Richard Birgander ◽  
Anders Eklund ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Cerebral Artery ◽  
Flow Rate ◽  
Cerebral Perfusion ◽  
Brain Volume ◽  
Cerebral Arteries ◽  
Blood Flow Rate ◽  
Collateral Flow ◽  
Vascular Tree

High-resolution phase—contrast magnetic resonance imaging can now assess flow in proximal and distal cerebral arteries. The aim of this study was to describe how total cerebral blood flow (tCBF) is distributed into the vascular tree with regard to age, sex and anatomic variations. Forty-nine healthy young (mean 25 years) and 45 elderly (mean 71 years) individuals were included. Blood flow rate (BFR) in 21 intra- and extracerebral arteries was measured. Total cerebral blood flow was defined as BFR in the internal carotid plus vertebral arteries and mean cerebral perfusion as tCBF/brain volume. Carotid/vertebral distribution was 72%/28% and was not related to age, sex, or brain volume. Total cerebral blood flow (717±123 mL/min) was distributed to each side as follows: middle cerebral artery (MCA), 21%; distal MCA, 6%; anterior cerebral artery (ACA), 12%, distal ACA, 4%; ophthalmic artery, 2%; posterior cerebral artery (PCA), 8%; and 20% to basilar artery. Deviating distributions were observed in subjects with ‘fetal’ PCA. Blood flow rate in cerebral arteries decreased with increasing age ( P<0.05) but not in extracerebral arteries. Mean cerebral perfusion was higher in women (women: 61±8; men: 55±6 mL/min/100 mL, P<0.001). The study describes a new method to outline the flow profile of the cerebral vascular tree, including reference values, and should be used for grading the collateral flow system.

scholarly journals Cerebral blood flow and cognitive outcome after pediatric stroke in the middle cerebral artery

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Leonie Steiner ◽  
Andrea Federspiel ◽  
Jasmine Jaros ◽  
Nedelina Slavova ◽  
Roland Wiest ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Middle Cerebral Artery ◽  
Cerebral Artery ◽  
Cognitive Functions ◽  
Cognitive Outcome ◽  
Cerebral Hypoperfusion ◽  
Pediatric Stroke ◽  
Healthy Controls ◽  
Long Term Outcome

AbstractAdaptive recovery of cerebral perfusion after pediatric arterial ischemic stroke (AIS) is sought to be crucial for sustainable rehabilitation of cognitive functions. We therefore examined cerebral blood flow (CBF) in the chronic stage after stroke and its association with cognitive outcome in patients after pediatric AIS. This cross-sectional study investigated CBF and cognitive functions in 14 patients (age 13.5 ± 4.4 years) after pediatric AIS in the middle cerebral artery (time since AIS was at least 2 years prior to assessment) when compared with 36 healthy controls (aged 13.8 ± 4.3 years). Cognitive functions were assessed with neuropsychological tests, CBF was measured with arterial spin labeled imaging in the anterior, middle, and posterior cerebral artery (ACA, MCA, PCA). Patients had significantly lower IQ scores and poorer cognitive functions compared to healthy controls (p < 0.026) but mean performance was within the normal range in all cognitive domains. Arterial spin labeled imaging revealed significantly lower CBF in the ipsilesional MCA and PCA in patients compared to healthy controls. Further, we found significantly higher interhemispheric perfusion imbalance in the MCA in patients compared to controls. Higher interhemispheric perfusion imbalance in the MCA was significantly associated with lower working memory performance. Our findings revealed that even years after a pediatric stroke in the MCA, reduced ipsilesional cerebral blood flow occurs in the MCA and PCA and that interhemispheric imbalance is associated with cognitive performance. Thus, our data suggest that cerebral hypoperfusion might underlie some of the variability observed in long-term outcome after pediatric stroke.

scholarly journals Inter- and Intra-Rater Reliability of Individual Cerebral Blood Flow Measured by Quantitative Vessel-Flow Phase-Contrast MRI

2020 ◽  
Vol 9 (10) ◽  
pp. 3099
Author(s):  
Kwang-Hwa Chang ◽  
Yuan-Hao Lee ◽  
Chia-Yuen Chen ◽  
Ming-Fang Lin ◽  
Ying Chin Lin ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Magnetic Resonance ◽  
Magnetic Resonance Angiography ◽  
Correlation Coefficient ◽  
Cerebral Artery ◽  
Phase Contrast ◽  
Cerebral Arteries ◽  
Intraclass Correlation ◽  
Vessel Flow

Vessel flow quantification by two-dimensional (2D) phase-contrast magnetic resonance imaging (PC-MRI) using a three-dimensional (3D) magnetic resonance angiography (MRA) model to measure cerebral blood flow has unclear analytical reliability. The present study aimed to determine the inter- and intra-rater reliability of quantitative vessel-flow PC-MRI and potential factors influencing its consistency. We prospectively recruited 30 Asian participants (aged 20–90 years; 16 women; 22 healthy and 8 stroke patients) for performing 1.5-T MR equipped with a head coil. Each participant was first scanned for time-of-flight magnetic resonance angiography (TOF-MRA) images for localization of intracranial arteries. The 2D PC-MRI for each cerebral artery (total 13 arteries in fixed order) was performed twice by two well-trained operators in optimal position. Using the same 3D MRA as a map and facilitated with the non-invasive optimal vessel analysis (NOVA) system, each scan was taken on a plane perpendicular to the target artery. Two consecutive full 13-artery scans were performed at least 15 min apart after participants were removed from the scanner table and then repositioned. A total of four PC flow images obtained from each target artery were transmitted to a workstation facilitated with the NOVA system. Flow data were calculated semi-automatically by the NOVA system after a few simple steps. Two-way mixed-effect models and standard errors of measurements were used. In 13 cerebral arteries, repeatability, using the intra-rater estimate expressed as the average-measures intraclass correlation coefficient, ranged from 0.641 to 0.954, and reproducibility, using the inter-rater estimate, ranged from 0.672 to 0.977. Except in the middle cerebral artery and the distal segment of the anterior cerebral artery, repeatability and reproducibility were excellent (intraclass correlation coefficient exceeded 0.8). The use of quantitative vessel-flow PC-MRI is a precise means to measure blood flow in most target cerebral arteries. This was evidenced by inter-rater and intra-rater correlations that were good/excellent, indicating good reproducibility and repeatability.

scholarly journals Effects of LI11 Acupuncture on CO2 reactivity in the anterior and middle cerebral arteries during hyperventilation-induced hypocapnia in normal subjects: A before and after study

2021 ◽  
Vol 42 (4) ◽  
pp. 174-185
Author(s):  
Gyeong-muk Kim ◽  
Woo-Sang Jung ◽  
Seungwon Kwon ◽  
Chul Jin ◽  
Seung-Yeon Cho ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Flow Velocity ◽  
Cerebral Artery ◽  
Blood Flow Velocity ◽  
Cerebral Blood Flow Velocity ◽  
Cerebral Arteries ◽  
Co2 Reactivity ◽  
Middle Cerebral Arteries ◽  
Before And After

Objectives: The LI11 (Quchi) acupuncture point has always been included in the Seven acupoints for stroke; however, additional LI11 acupuncture research is needed. In this study, the effect of LI11 acupuncture on cerebral blood flow of the anterior cerebral arteries (ACA) and middle cerebral arteries (MCA) was investigated.Method: This study included 10 healthy young male subjects. Cerebral blood flow velocity and cerebrovascular reactivity were measured using transcranial Doppler sonography. Changes in hyperventilation-induced carbon dioxide (CO2) reactivity and modified ACA and MCA blood flow velocity at 40 mmHg (CV40), blood pressure, and heart rate were observed before and after LI11 acupuncture treatment.Results: A statistically significant increase in contralateral anterior cerebral artery CO2 reactivity (p=0.036) and decrease in contralateral middle cerebral artery CV40 (p=0.047) were observed. No significant difference in mean blood pressure was shown. A statistically significant increase in heart rate occurred after LI11 acupuncture; however, it was not clinically significant as there were negligible changes in the heart rhythm.Conclusions: LI11 acupuncture treatment could improve cerebral blood flow velocity. These results might be explained by regulating endothelium-dependent vessel dilation in the anterior cerebral artery region.Trial registration: This trial has been registered with Clinical Research Information Service, a service of the Korea Centers for Disease Control and Prevention: KCT0004494 (retrospectively registered). https://cris.nih.go.kr/cris/search/search_result_st01.jsp?seq=15359

The Effect of Circulating Adenosine on Cerebral Haemodynamics and Headache Generation in Healthy Subjects

Cephalalgia ◽  
2005 ◽  
Vol 25 (5) ◽  
pp. 369-377 ◽  
Author(s):  
S Birk ◽  
KA Petersen ◽  
C Kruuse ◽  
R Guieu ◽  
O Jonassen ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Cerebral Artery ◽  
Single Photon ◽  
Cerebral Arteries ◽  
Superficial Temporal Artery ◽  
Photon Emission ◽  
Temporal Artery ◽  
Emission Computed Tomography ◽  
Double Blind

Adenosine is an endogenous neurotransmitter that is released from the brain during hypoxia and relaxes isolated human cerebral arteries. Many cerebral artery dilators cause migraine attacks. However, the effect of intravenous adenosine on headache and cerebral artery diameter has not previously been investigated in man and reports regarding the effect of intravenous adenosine on cerebral blood flow are conflicting. Twelve healthy participants received adenosine 80, 120 μg kg-1 min-1 and placebo intravenously for 20 min, in a double-blind, three-way, crossover, randomized design. Headache was rated on a verbal scale (0-10). Regional cerebral blood flow (rCBF) with 133Xe inhalation and single-photon emission computed tomography (SPECT) and MCA flow velocity (VMCA) with transcranial Doppler, were measured in direct sequence. Six participants developed headache during 80 μg kg-1 min-1 and six during 120 μg kg-1 min-1 compared with none on placebo ( P = 0.006). The headache was very mild and predominantly described as a pressing sensation. When correcting data for adenosine-induced hyperventilation, no significant changes in rCBF ( P = 0.22) or VMCA ( P = 0.16) were found between treatments. A significant dilation of the superficial temporal artery (STA) was seen ( P < 0.001). These results show that circulating adenosine has no effect on rCBF or VMCA, while it dilates the STA and causes very mild headache.

Effect of hematocrit variations on cerebral blood flow and basilar artery diameter in vivo

1992 ◽  
Vol 262 (4) ◽  
pp. H949-H954 ◽  
Author(s):  
J. P. Muizelaar ◽  
G. J. Bouma ◽  
J. E. Levasseur ◽  
H. A. Kontos
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Basilar Artery ◽  
Cerebral Arteries ◽  
Blood Rheology ◽  
Inverse Correlation ◽  
Large Artery ◽  
Altered Blood ◽  
Reported Data

Despite observations that pial arterioles constrict with decreased blood viscosity or hemodilution, several investigators have found an inverse relationship between cerebral blood flow (CBF) and hematocrit (Hct) under physiological conditions. To investigate whether this is due to a dilation of the more proximal large cerebral arteries, in vivo responses of CBF and basilar artery to hemodilution and hemoconcentration were studied in 21 anesthetized normal cats, using a closed clival window model. An inverse correlation between Hct and CBF was found, but CBF responses were smaller than previously reported data suggest. Varying Hct between 60 and 120% of baseline caused CBF to vary between 140 and 90%, approximately. Moderate hemodilution was associated with a significant decrease (-4.4%) in basilar artery diameter (P less than 0.05), but other Hct manipulations had no consistent effect on basilar artery diameter. It is concluded that dilation of large cerebral arteries cannot account for the decreased cerebrovascular resistance following hemodilution but that a disproportionate reduction of in vivo viscosity must be responsible. Pial arteriolar constriction after hemodilution therefore probably reflects a normal autoregulatory adjustment of vasomotor tone to altered blood rheology, whereas changes in large artery caliber may serve to modulate microvascular pressure.

scholarly journals Endothelium-Derived Relaxing Factor Inhibits Constrictor Responses of Large Cerebral Arteries to Serotonin

1992 ◽  
Vol 12 (3) ◽  
pp. 500-506 ◽  
Author(s):  
Frank M. Faraci ◽  
Donald D. Heistad
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Vascular Resistance ◽  
Cerebral Arteries ◽  
Large Arteries ◽  
Relaxing Factor ◽  
Endothelium Derived Relaxing Factor ◽  
Cerebral Vascular Resistance ◽  
Cerebral Vascular

Endothelium-derived relaxing factor [EDRF, nitric oxide (NO) or a NO-containing compound] influences basal tone of cerebral blood vessels and mediates vasodilation in response to several stimuli. It is not known whether EDRF also modulates responses to cerebral vasoconstrictor stimuli in vivo. Our goal was to determine whether formation of EDRF inhibits constrictor responses of large cerebral arteries to serotonin. We measured cerebral blood flow (microspheres) and pial microvascular pressure (servo null) in anesthetized rabbits and calculated resistance of large cerebral arteries. Responses to an inhibitor of NO formation, NG-nitro-l-arginine (l-NNA, 3 mg/kg i.v.), were examined. l-NNA produced an increase in resistance of large arteries and total cerebral vascular resistance of approximately 15% (p < 0.05 for both variables) and a small decrease in cerebral blood flow (35 ± 9 vs. 32 ± 7 ml min−1 100 g−1, mean ± SD, p < 0.05). Under control conditions, infusion of serotonin (10 μg kg−1 min−1, into the left atrium) produced an increase in resistance of large arteries. Following treatment with l-NNA, the change in resistance of large arteries in response to serotonin was increased more than twofold (0.20 ± 0.17 vs. 0.43 ± 0.21 mm Hg ml−1 min 100 g, p < 0.05). In contrast, l-NNA did not alter the increase in resistance of large arteries during hypocapnia. l-arginine inhibited the effects of l-NNA on baseline cerebral vascular resistance and on responses of large arteries to serotonin. Thus, formation of EDRF (NO) from l-arginine (a) has a modest influence on cerebral blood flow under basal conditions and (b) inhibits constriction of large cerebral arteries to serotonin, but not hypocapnia.

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