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 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 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 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

scholarly journals Diagnostic and prognostic potential of non-invasive assessment of cerebral blood flow autoregulation

2015 ◽  
Vol 14 (1) ◽  
pp. 4-14
Author(s):  
V. B. Semenyutin ◽  
V. A. Aliev ◽  
V. P. Bersnev ◽  
A. . Patzak ◽  
G. K. Panuntsev ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Brain Injury ◽  
Cerebral Arteries ◽  
Systemic Blood Pressure ◽  
Communicating Hydrocephalus ◽  
Non Invasive ◽  
Pathological Conditions ◽  
Neurosurgical Patients ◽  
Cerebral Blood Flow Autoregulation

Purpose. To study the potential of non-invasive assessment of cerebral blood flow autoregulation (CA) using cross-spectral analysis of slow dopplerographic patterns. Materials and methods. The study involved 40 healthy volunteers and 228 patients with different neurosurgical pathology: cerebral aneurysm - 50 cases, arteriovenous malformation - 52, traumatic brain injury - 61, communicating hydrocephalus - 24, parasagittal meningioma - 20, stenosis and thrombosis of the carotid arteries - 21. Blood flow velocity (BFV) in middle cerebral arteries was monitored using Multi Dop X (DWL, Germany), systemic blood pressure (BP) - noninvasively with Finapres (Ohmeda 2100 USA) within 4 minutes. CA was assessed by calculating the phase shift (PSM) between spontaneous slow oscillations of BP and BFV within the range of systemic Mayer waves (80-120 mHz) and amplitude of intracranial B-waves of BFV (AB) within the range from 8 to 50 mHz). Results and discussion. CA demonstrated different patterns in neurosurgical patients and varied from normal autoregulation to its complete absence. This indicates the degree of compensation of cerebral hemodynamics in pathological conditions such as intracranial hypertension, vasospasm, traumatic edema, ischemia, abnormal arteriovenous shunting. On the basis of perioperative evaluation of PSM and AB, the predictors of efficacy and outcome have been identified in patients with cerebral aneurysms in an acute period of hemorrhage, severe brain injury, cerebral arteriovenous malformations and communicating hydrocephalus. Conclusions. Analysis of slow-wave dopplerographic patterns of BFV in intracranial cerebral arteries and BP is informative, adequate, safe non-invasive way to assess CA in normal and pathological conditions. Perioperative assessment of these patterns can be used to predict the effectiveness of treatment in patients with different neurosurgical pathology.

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.

scholarly journals The Cerebral Circulation During Pregnancy: Adapting to Preserve Normalcy

Physiology ◽  
2015 ◽  
Vol 30 (2) ◽  
pp. 139-147 ◽  
Author(s):  
Abbie C. Johnson ◽  
Marilyn J. Cipolla
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Blood Brain Barrier ◽  
Cerebral Circulation ◽  
Cerebral Arteries ◽  
Structure And Function ◽  
Cerebral Blood Flow Autoregulation ◽  
And Function ◽  
The Brain ◽  
Brain Homeostasis

The adaptation of the brain and cerebral circulation to pregnancy are unique compared with other organs and circulatory systems, ultimately functioning to maintain brain homeostasis. In this review, the effect of pregnancy on critical functions of the cerebral circulation is discussed, including changes occurring at the endothelium and blood-brain barrier, and changes in the structure and function of cerebral arteries and arterioles, hemodynamics, and cerebral blood flow autoregulation.

scholarly journals Transcranial Doppler Evaluation of the Cerebral Vasculature in Women Patients who Have Migraine with Aura

Pain Medicine ◽  
2020 ◽  
Vol 21 (11) ◽  
pp. 3012-3017
Author(s):  
Igor Petrušić ◽  
Ana Podgorac ◽  
Aleksandra Radojičić ◽  
Jasna Zidverc-Trajković
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Migraine With Aura ◽  
Transcranial Doppler ◽  
Cerebral Blood Flow Velocity ◽  
Cerebral Arteries ◽  
Transcranial Doppler Sonography ◽  
Cerebrovascular Reactivity ◽  
Breath Holding ◽  
Left And Right

Abstract Background Previous studies suggest that increased cerebrovascular reactivity might be a feature of patients who have migraine with aura (MwA). The correlation between the clinical presentation of migraine with aura and transcranial Doppler parameters remains unclear. Objective The main aim of this study was to explore cerebral blood flow, vascular resistance, and cerebrovascular reactivity in women MwA. Also, the relationships between hemodynamic conditions and aura characteristics are examined. Design Cross-sectional study. Setting Headache Center, Neurology Clinic, Clinical Center of Serbia. Subjects Fifty-four women MwA and 49 healthy controls (HCs). Methods Transcranial Doppler sonography examination was used to determine blood flow mean velocity (MV) and pulsatility index (PI), as well as breath-holding index (BHI), in 15 arterial segments comprising the circle of Willis. Results A total of 54 women MwA and 49 HCs were studied. The PIs of all segments of the left and right middle cerebral arteries and the left and right anterior cerebral arteries were significantly higher in MwA with regards to HCs. Also, both the left and right BHIs were significantly higher in MwA than HCs. In addition, MVs of the right vertebral artery and the first segment of the basilar artery were significantly lower in MwA than HCs. Longer duration of migraine aura showed a weak negative correlation with the PI of the left posterior cerebral artery. Conclusions Our findings suggest increased vessel pulsatility, abnormal cerebrovascular reactivity, and decreased cerebral blood flow velocity in several arterial segments of the Willis circle in women MwA.

Sign in / Sign up

Export Citation Format

Share Document