scholarly journals Ablation of Vitamin D Signaling Compromises Cerebrovascular Adaptation to Carotid Artery Occlusion in Mice

Cells ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 1457
Author(s):  
Éva Pál ◽  
László Hricisák ◽  
Ágnes Lékai ◽  
Dorina Nagy ◽  
Ágnes Fülöp ◽  
...  
Keyword(s):  
Vitamin D ◽  
Blood Flow ◽  
Carotid Artery ◽  
Collateral Circulation ◽  
Temporal Cortex ◽  
Artery Occlusion ◽  
Carotid Artery Occlusion ◽  
Arterial Blood Flow ◽  
Blood Flow Increase ◽  
Vitamin D Signaling

Vitamin D insufficiency has been associated with increased incidence and severity of cerebrovascular disorders. We analyzed the impact of impaired vitamin D signaling on the anatomical and functional aspects of cerebrovascular adaptation to unilateral carotid artery occlusion (CAO), a common consequence of atherosclerosis and cause of ischemic stroke. Cerebrocortical blood flow (CoBF) showed a significantly increased drop and delayed recovery after CAO in mice carrying a functionally inactive vitamin D receptor (VDR) with the most sustained perfusion deficit in the temporal cortex. To identify the cause(s) for this altered adaptation, the extent of compensatory blood flow increase in the contralateral carotid artery and the morphology of pial collaterals between the anterior and middle cerebral arteries were determined. Whereas VDR deficiency had no significant influence on the contralateral carotid arterial blood flow increase, it was associated with decreased number and increased tortuosity of pial anastomoses resulting in unfavorable changes of the intracranial collateral circulation. These results indicate that VDR deficiency compromises the cerebrovascular adaptation to CAO with the most sustained consequences in the temporal cortex. The dysregulation can be attributed to the altered development and function of pial collateral circulation whereas extracranial vessels may not be impaired.

scholarly journals Study on the correlation between the circle of Willis structure and collateral circulation in bilateral carotid artery occlusion

2021 ◽  
Author(s):  
Yang Liu ◽  
Lei Zhu ◽  
Bei Hou ◽  
Tuoyi Wang ◽  
Dechao Xu ◽  
...  
Keyword(s):  
Blood Flow ◽  
Carotid Artery ◽  
Cerebral Artery ◽  
Collateral Circulation ◽  
Artery Occlusion ◽  
Carotid Artery Occlusion ◽  
Complete Type ◽  
Bilateral Carotid ◽  
Flow Compensation

Abstract Background and purpose Bilateral carotid artery occlusion (CAO) is a rare condition and the collateral circulation is more complicated than in unilateral CAO. The circle of Willis (CoW) is the most important collateral circulation compensation pathway in CAO. However, the specific role of CoW in the collateral circulation compensation pathway of CAO has not been fully elucidated. The purpose of this study is to investigate the role of CoW in the collateral circulation compensation pathway of CAO. Materials and methods Clinical, imaging, and hemodynamic data of 30 patients with bilateral CAO were collected to analyze the collateral blood flow compensation pathway and its characteristics, and to examine the correlation between the structure of the CoW and the collateral circulation of bilateral CAO. Results This paper summarized 30 patients with bilateral CAO. There were 0 cases of the CoW complete type, 18 cases of the partially complete type (60%), and 12 cases of the incomplete type (40%). For the partially complete type cases, there were 14 complete anterior circulation cases (46.7%). The collateral circulation collateral circulation pathway included 14 cases with anterior communicating artery(ACoA), 7 cases with posterior cerebral artery (PCA)-middle cerebral artery (MCA) leptomeningeal anastomosis (LMA), 5 cases with ophthalmic artery(OA), 3 cases with lateral posterior communicating artery(PCoA), 1 case with internal carotid artery (ICA) stealing, 1 case with new Moyamoya vessels, and 4 cases of other types. There were four cases (13.3%) with complete posterior circulation, including four cases with bilateral PCoA, three cases with PCA-MCA LMA, and two cases with OA. There were 12 cases (40%) with incomplete CoW, including 8 cases with PCA-MCA LMA, 3 cases with lateral PCoA, 1 case with anterior cerebral artery (ACA)-MCA LMA, 4 cases with OA, and 1 other case. Conclusion The collateral circulation pathway differs among patients with different CoW structure types. When the CoW is partially complete, it mainly provides blood flow compensation to the ischemic area through primary collateral circulation. When the CoW is incomplete, it mainly provides blood flow compensation to the ischemic area through secondary collateral circulation.

scholarly journals Adaptation of the cerebrocortical circulation to carotid artery occlusion involves blood flow redistribution between cortical regions and is independent of eNOS

2016 ◽  
Vol 311 (4) ◽  
pp. H972-H980 ◽  
Author(s):  
Andreas Polycarpou ◽  
László Hricisák ◽  
András Iring ◽  
Daniel Safar ◽  
Éva Ruisanchez ◽  
...  
Keyword(s):  
Blood Flow ◽  
Carotid Artery ◽  
Blood Supply ◽  
Right Hemisphere ◽  
Temporal Cortex ◽  
Artery Occlusion ◽  
Carotid Artery Occlusion ◽  
Laser Speckle ◽  
Collateral Vessels ◽  
The Right

Cerebral circulation is secured by feed-forward and feed-back control pathways to maintain and eventually reestablish the optimal oxygen and nutrient supply of neurons in case of disturbances of the cardiovascular system. Using the high temporal and spatial resolution of laser-speckle imaging we aimed to analyze the pattern of cerebrocortical blood flow (CoBF) changes after unilateral (left) carotid artery occlusion (CAO) in anesthetized mice to evaluate the contribution of macrovascular (circle of Willis) vs. pial collateral vessels as well as that of endothelial nitric oxide synthase (eNOS) to the cerebrovascular adaptation to CAO. In wild-type mice CoBF reduction in the left temporal cortex started immediately after CAO, reaching its maximum (−26%) at 5–10 s. Thereafter, CoBF recovered close to the preocclusion level within 30 s indicating the activation of feed-back pathway(s). Interestingly, the frontoparietal cerebrocortical regions also showed CoBF reduction in the left (−17–19%) but not in the right hemisphere, although these brain areas receive their blood supply from the common azygos anterior cerebral artery in mice. In eNOS-deficient animals the acute CoBF reduction after CAO was unaltered, and the recovery was even accelerated compared with controls. These results indicate that 1) the Willis circle alone is not sufficient to provide an immediate compensation for the loss of one carotid artery, 2) pial collaterals attenuate the ischemia of the temporal cortex ipsilateral to CAO at the expense of the blood supply of the frontoparietal region, and 3) eNOS, surprisingly, does not play an important role in this CoBF redistribution.

Assessing the Effects of Antihypertensive Medication on Cerebral Blood Flow: Demonstration in Internal Carotid Artery Occlusion

DICP ◽  
1991 ◽  
Vol 25 (12) ◽  
pp. 1299-1301 ◽  
Author(s):  
Susan C. Fagan ◽  
James R. Ewing ◽  
Steven R. Levine ◽  
Gretchen E. Tietjen ◽  
Nabih M. Ramadan ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Carotid Artery ◽  
Internal Carotid Artery ◽  
Antihypertensive Medication ◽  
Internal Carotid ◽  
Artery Occlusion ◽  
Carotid Artery Occlusion ◽  
Internal Carotid Artery Occlusion ◽  
Bilateral Carotid

Dynamic cerebral blood flow (CBF) studies using acetazolamide or hypercapnia as a vasodilatory challenge have attempted to evaluate intracranial hemodynamics. We report two patients with asymptomatic internal carotid artery occlusion in whom the vasodilatory stimulus was a single oral dose of antihypertensive medication (prazosin hydrochloride or enalapril maléate). In both patients, changes in regional CBF occurred that were larger than those seen in nine normal controls. One patient experienced an improvement in regional CBF with a reduction in probe pair asymmetry. In the other patient, who had bilateral carotid artery disease, a decrease in regional CBF in all 16 probes (mean decrease 12 percent) and an accentuation of the predose asymmetry were observed. Both patients remained asymptomatic throughout the study. Assessing these effects on cerebral circulation may help identify patients at risk for iatrogenic focal cerebral ischemia and provide information regarding the functional status of the cerebral vasculature.

Mechanism of intrarenal blood flow redistribution after carotid artery occlusion

1977 ◽  
Vol 232 (2) ◽  
pp. F167-F172 ◽  
Author(s):  
E. H. Prosnitz ◽  
E. J. Zambraski ◽  
G. F. DiBona
Keyword(s):  
Blood Flow ◽  
Carotid Artery ◽  
Renal Blood Flow ◽  
Perfusion Pressure ◽  
Renal Perfusion ◽  
Artery Occlusion ◽  
Carotid Artery Occlusion ◽  
Outer Cortex ◽  
Renal Sympathetic Nerve Activity ◽  
Renal Perfusion Pressure

Bilateral carotid artery occlusion results in an increase in mean arterial pressure, an increase in renal sympathetic nerve activity, and a redistribution of renal blood flow from inner to outer cortex. To elucidate the mechanism of the renal blood flow redistribution, carotid artery occlusion was performed in anesthetized dogs with the left kidney either having renal perfusion pressure maintained constant (aortic constriction) or having alpha-adrenergic receptor blockade (phenoxybenzamine); the right kidney of the same dog served to document the normal response. When renal perfusion pressure was maintained constant, renal blood flow distribution (microspheres) was unchanged by carotid artery occlusion. In the presence of renal alpha-adrenergic receptor blockade, carotid artery occlusion elicited the usual redistribution of renal blood flow from inner to outer cortex. The redistribution of renal blood flow observed after carotid artery occlusion is mediated by the increase in renal perfusion pressure rather than the increase in renal sympathetic nerve activity.

Axilloaxillary Bypass for the Treatment of Subclavian Artery Stenosis Complicated by Bilateral Common Carotid Artery Occlusion: Technical Case Report

Neurosurgery ◽  
2003 ◽  
Vol 53 (2) ◽  
pp. 444-447 ◽  
Author(s):  
Masahiro Ogino ◽  
Masashi Nagumo ◽  
Toru Nakagawa ◽  
Masashi Nakatsukasa ◽  
Ikuro Murase
Keyword(s):  
Blood Flow ◽  
Carotid Artery ◽  
Vertebral Artery ◽  
Subclavian Artery ◽  
Bypass Surgery ◽  
Left Subclavian Artery ◽  
Artery Occlusion ◽  
Carotid Artery Occlusion ◽  
Bilateral Common Carotid Artery ◽  
Common Carotid Artery Occlusion

Abstract OBJECTIVE AND IMPORTANCE We successfully treated a patient with stenosis of the left subclavian artery, complicated by bilateral common carotid artery occlusion, via axilloaxillary bypass surgery. CLINICAL PRESENTATION A 67-year-old patient with a history of hypertension and cerebral infarction underwent neck irradiation for treatment of a vocal cord tumor. Three months later, he began to experience transient tetraparesis several times per day. The blood pressure measurements for his right and left arms were different. Supratentorial blood flow was markedly low. The common carotid arteries were bilaterally occluded, and the right vertebral artery was hypoplastic. Therefore, only the left vertebral artery contributed to the patient's cerebral circulation; his left subclavian artery was severely stenotic. INTERVENTION The patient underwent axilloaxillary bypass surgery because the procedure avoids thoracotomy or sternotomy, manipulation of the carotid artery, and interruption of the vertebral artery blood flow. The patient has been free of symptoms for more than 5 years. CONCLUSION Neurosurgeons should be aware that extra-anatomic bypass surgery is an effective treatment option for selected patients with cerebral ischemia.

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