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MeSH Review

Circle of Willis

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Disease relevance of Circle of Willis

  • Presence of neuropeptide Y in human circle of Willis and its possible role in cerebral vasospasm [1].
  • The CO2 response was normal in patients with angiographic signs of circle of Willis collateral flow and without significant contralateral carotid stenosis, whereas it was impaired in patients with a retrograde ophthalmic flow or collateral flow via the circle of Willis and contralateral carotid stenosis greater than or equal to 50% [2].
  • Two weeks after bilateral removal of the sphenopalatine ganglion or sectioning of the structures in the ethmoidal foramen, VIP fibers in the anterior part of the circle of Willis completely disappeared [3].
  • CONCLUSION: Large asymmetries in volume flow between the right and left ICAs or decreased volume flow in the BA is not necessarily caused by vascular disease but may be caused by variations in the anatomy of the circle of Willis [4].
  • Multiple areas of stenosis and occlusion in all branches of the circle of Willis, and hypertrophy of collateral perforating vessels at the base of the brain in a "puff of smoke" appearance typical of moyamoya disease were seen on cerebral angiogram 5 months before the patient died [5].

High impact information on Circle of Willis


Biological context of Circle of Willis


Anatomical context of Circle of Willis


Associations of Circle of Willis with chemical compounds

  • 5-Hydroxytryptamine concentrations in rats, cats, and rabbits were significantly greater in the small pial vessels, although measurable concentrations existed in the circle of Willis [16].
  • CONCLUSIONS: These results suggest that the arteries composing the circle of Willis at the base of the brain are more sensitive to nitric oxide release induced by vasopressin compared with other intracranial and extracranial arteries [20].
  • CONCLUSIONS: C57Black/6 mice exhibit enhanced susceptibility to global cerebral ischemic injury, an incompletely formed circle of Willis, and augmented pial vessel dilation to ACh compared with SV-129 mice [21].
  • The aims of this study were to characterize the melatonin receptors in rat brain arteries forming the circle of Willis [11].
  • Two days after bilateral removal of the superior and middle cervical ganglia of 7-week-old rats, noradrenaline-containing nerves could not be detected along any of the arteries of the rat circle of Willis or of the iris, but 18-32% of neuropeptide Y-like immunoreactive nerves remained [22].

Gene context of Circle of Willis


Analytical, diagnostic and therapeutic context of Circle of Willis


  1. Presence of neuropeptide Y in human circle of Willis and its possible role in cerebral vasospasm. Allen, J.M., Schon, F., Todd, N., Yeats, J.C., Crockard, H.A., Bloom, S.R. Lancet (1984) [Pubmed]
  2. rCBF in patients with carotid occlusion. Resting and hypercapnic flow related to collateral pattern. Norrving, B., Nilsson, B., Risberg, J. Stroke (1982) [Pubmed]
  3. Origins and pathways of cerebrovascular vasoactive intestinal polypeptide-positive nerves in rat. Suzuki, N., Hardebo, J.E., Owman, C. J. Cereb. Blood Flow Metab. (1988) [Pubmed]
  4. Distribution of cerebral blood flow in the circle of Willis. Hendrikse, J., van Raamt, A.F., van der Graaf, Y., Mali, W.P., van der Grond, J. Radiology. (2005) [Pubmed]
  5. Quaternary neurosyphilis in a Haitian man with human immunodeficiency virus infection. Morgello, S., Laufer, H. Hum. Pathol. (1989) [Pubmed]
  6. Cranial computed tomography and magnetic resonance imaging in autosomal dominant polycystic kidney disease. Torres, V.E., Wiebers, D.O., Forbes, G.S. J. Am. Soc. Nephrol. (1990) [Pubmed]
  7. Normalization of endothelial and inducible nitric oxide synthase expression in brain microvessels of spontaneously hypertensive rats by angiotensin II AT1 receptor inhibition. Yamakawa, H., Jezova, M., Ando, H., Saavedra, J.M. J. Cereb. Blood Flow Metab. (2003) [Pubmed]
  8. Linkage of familial moyamoya disease (spontaneous occlusion of the circle of Willis) to chromosome 17q25. Yamauchi, T., Tada, M., Houkin, K., Tanaka, T., Nakamura, Y., Kuroda, S., Abe, H., Inoue, T., Ikezaki, K., Matsushima, T., Fukui, M. Stroke (2000) [Pubmed]
  9. Functional polymorphism in the matrix metalloproteinase-9 promoter as a potential risk factor for intracranial aneurysm. Peters, D.G., Kassam, A., St Jean, P.L., Yonas, H., Ferrell, R.E. Stroke (1999) [Pubmed]
  10. Frontal bone windows for transcranial color-coded duplex sonography. Stolz, E., Kaps, M., Kern, A., Dorndorf, W. Stroke (1999) [Pubmed]
  11. Characterization of melatonin receptors and signal transduction system in rat arteries forming the circle of Willis. Capsoni, S., Viswanathan, M., De Oliveira, A.M., Saavedra, J.M. Endocrinology (1994) [Pubmed]
  12. Performance evaluation of a positron tomograph designed for brain imaging. Hoffman, E.J., Phelps, M.E., Huang, S.C. J. Nucl. Med. (1983) [Pubmed]
  13. Krypton-81m single photon emission tomography and the collateral circulation in carotid occlusion: the role of the circle of Willis and leptomeningeal anastomosis. Fukuyama, H., Akiguchi, I., Kameyama, M., Taki, W., Handa, H., Higa, T., Tanada, S., Fujita, T., Torizuka, K. J. Neurol. (1983) [Pubmed]
  14. Current state of study on moyamoya disease in Japan. Fukui, M. Surgical neurology. (1997) [Pubmed]
  15. Perivascular substance P: occurrence and distribution in mammalian pial vessels. Uddman, R., Edvinsson, L., Owman, C., Sundler, F. J. Cereb. Blood Flow Metab. (1981) [Pubmed]
  16. Concentrations of putative neurovascular transmitters in major cerebral arteries and small pial vessels of various species. Duverger, D., Edvinsson, L., MacKenzie, E.T., Oblin, A., Rouquier, L., Scatton, B., Zivkovic, B. J. Cereb. Blood Flow Metab. (1987) [Pubmed]
  17. Substance P: immunohistochemical localization and effect upon cat pial arteries in vitro and in situ. Edvinsson, L., McCulloch, J., Uddman, R. J. Physiol. (Lond.) (1981) [Pubmed]
  18. Dilating effect of perivascularly applied potassium channel openers cromakalim and pinacidil in rat and cat pial arteries in situ. Wahl, M., Parsons, A.A., Schilling, L. Cardiovasc. Res. (1994) [Pubmed]
  19. Small-vessel radiography in situ with monochromatic synchrotron radiation. Mori, H., Hyodo, K., Tanaka, E., Uddin-Mohammed, M., Yamakawa, A., Shinozaki, Y., Nakazawa, H., Tanaka, Y., Sekka, T., Iwata, Y., Handa, S., Umetani, K., Ueki, H., Yokoyama, T., Tanioka, K., Kubota, M., Hosaka, H., Ishikawa, N., Ando, M. Radiology. (1996) [Pubmed]
  20. Regional differences in the vasodilator response to vasopressin in canine cerebral arteries in vivo. Suzuki, Y., Satoh, S., Oyama, H., Takayasu, M., Shibuya, M. Stroke (1993) [Pubmed]
  21. Strain-related differences in susceptibility to transient forebrain ischemia in SV-129 and C57black/6 mice. Fujii, M., Hara, H., Meng, W., Vonsattel, J.P., Huang, Z., Moskowitz, M.A. Stroke (1997) [Pubmed]
  22. Long-term chemical sympathectomy leads to an increase of neuropeptide Y immunoreactivity in cerebrovascular nerves and iris of the developing rat. Mione, M.C., Cavanagh, J.F., Lincoln, J., Milner, P., Burnstock, G. Neuroscience (1990) [Pubmed]
  23. Neuropeptide Y and vasoactive intestinal peptide in experimental subarachnoid hemorrhage: immunocytochemistry, radioimmunoassay and pharmacology. Edvinsson, L., Alafaci, C., Delgado, T., Ekman, R., Jansen, I., Svendgaard, N.A., Uddman, R. Acta neurologica Scandinavica. (1991) [Pubmed]
  24. Experimental cerebral aneurysms in the female heterozygous Blotchy mouse. Coutard, M. International journal of experimental pathology. (1999) [Pubmed]
  25. ICP monitoring following bilateral carotid occlusion in GFAP-null mice. Nawashiro, H., Huang, S., Brenner, M., Shima, K., Hallenbeck, J.M. Acta Neurochir. Suppl. (2002) [Pubmed]
  26. Systemic vascular changes in spontaneous occlusion of the circle of Willis. Ikeda, E. Stroke (1991) [Pubmed]
  27. Evaluation of cross-circulation through circle of Willis using an ultrasonic Doppler technique. Part I. Comparison between blood flow velocity by ultrasonic Doppler flowmetry and angiogram. Yoneda, S., Nukada, T., Kimura, K., Tanaka, K., Ashida, K., Asai, T., Etani, H., Imaizumi, M., Abe, H. Stroke (1981) [Pubmed]
  28. Alterations in serotonin and neuropeptide Y content of cerebrovascular sympathetic nerves following experimental subarachnoid hemorrhage. Jackowski, A., Crockard, A., Burnstock, G., Lincoln, J. J. Cereb. Blood Flow Metab. (1989) [Pubmed]
  29. 5-HT-containing nerves to major cerebral arteries of the gerbil originate in the superior cervical ganglia. Cowen, T., Alafaci, C., Crockard, H.A., Burnstock, G. Brain Res. (1986) [Pubmed]
  30. Assessment of cerebral haemodynamics and vascular reserve in patients with symptomatic carotid artery occlusion: an integrated MR method. Griffiths, P.D., Gaines, P., Cleveland, T., Beard, J., Venables, G., Wilkinson, I.D. Neuroradiology. (2005) [Pubmed]
  31. Comparative morphological variations and abnormalities of circles of Willis: a minireview including two personal cases. Vasović, L., Milenković, Z., Pavlović, S. Neurosurgical review. (2002) [Pubmed]
  32. Vasoactive intestinal polypeptide receptors in rat cerebral vessels: an autoradiographic study. Amenta, F., Cavalotti, C., De Michele, M., De Vincentis, G., Rossodivita, A., Rossodivita, I. Journal of autonomic pharmacology. (1991) [Pubmed]
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