scholarly journals Distribution of serotonin-like immunoreactive nerves in major cerebral arteries of rabbit: an immunohistochemical study.

1989 ◽  
Vol 37 (9) ◽  
pp. 1383-1386 ◽  
Author(s):  
U Dhall ◽  
G Burnstock
Keyword(s):  
Immunohistochemical Study ◽  
Anterior Part ◽  
Cerebral Arteries ◽  
Posterior Part ◽  
Nerve Fibers ◽  
Circle Of Willis ◽  
Immunofluorescence Technique ◽  
Whole Mount ◽  
Peptidergic Innervation ◽  
Indirect Immunofluorescence Technique

We studied the distribution pattern of serotonin-like immunoreactive nerve fibers in the major cerebral vessels of rabbit by an indirect immunofluorescence technique using whole-mount stretch preparations. The density of serotonin-like immunoreactive nerve fibers was greater in vessels of the posterior part of the circle of Willis compared with that in the anterior part. This is in contrast to most of the observations reported previously regarding adrenergic, cholinergic, and peptidergic innervation of the circle of Willis.

Exposure of the anterior part of the circle of Willis in the dog

1974 ◽  
Vol 41 (1) ◽  
pp. 107-112
Author(s):  
Shigeaki Hori ◽  
Williamina A. Himwich
Keyword(s):  
Anterior Part ◽  
Cerebral Arteries ◽  
Circle Of Willis ◽  
Content Type ◽  
Anatomical Characteristics ◽  
Fine Print

✓ A technique for exposing the vessels in the anterior part of the circle of Willis in the dog is described. Some of the physiological and anatomical characteristics of the anterior communicating and the anterior cerebral arteries are discussed.

scholarly journals Average dimensions of the vessels at the base of the brain and the embryological basis of its variations

2013 ◽  
Vol 02 (04) ◽  
pp. 180-189
Author(s):  
Iqbal S.
Keyword(s):  
Anterior Part ◽  
Cerebral Arteries ◽  
Cerebral Dominance ◽  
Circle Of Willis ◽  
Detailed Knowledge ◽  
Differential Growth ◽  
Ischemic Attack ◽  
The Individual ◽  
The Right ◽  
The Brain

Abstract Background and aims: The cerebral circulation is constantly maintained by the anastomotic circle of Willis which is often anomalous in more than 50% of the normal adult brains. These anomalies increase the risk of the stroke and transient ischemic attack in older patients. Adequate blood flow through the circle of Willis is often necessary to prevent these ischemic infarctions. The anomalies of cerebral vessels are directly related to the differential growth of various parts of the brain. A detailed knowledge of the individual measurements of the cerebral arteries is useful to neurosurgeon in planning the shunt operations and in the choice of their patients. The present study is aimed to analyze the average dimensions of the vessels at the base of brain and an attempt to explain the common form of variations in terms of embryological development. Materials and methods: Fifty adult cadaveric brains were obtained from routine cadaveric dissections. The base of the brain with the circle of Willis was fixed in 10% formalin and preserved. The circle was analyzed for variations in the size, length and number of the component vessels and any asymmetry in the configuration. The dimensions of the vessels forming the circle were measured using graduated calipers. The observations were recorded and tabulated. Results: Asymmetry was observed in 10% to 36% of the circles in this study. Anomalies were more common in the posterior than in the anterior part of the circle. The posterior anomalies included hypoplastic vessels, absent vessels and embryonic derivation while anterior anomalies were predominantly of accessory vessels. Middle cerebral artery exhibited the least variations. In majority of the circles, left sided vessels were larger in diameter than the right. Conclusions: Variations are more common in the posterior than in the anterior part of the circle and on the right than on the left side of the brain. There was no correlation between the variations of circle of Willis of the right side and the left cerebral dominance. There seems to be no difference between races, concerning the anatomic variations of the brain circulation.

scholarly journals Cholinergic and VIPergic Innervation in Cerebral Arteries: A Sequential Double-Labeling Immunohistochemical Study

1990 ◽  
Vol 10 (1) ◽  
pp. 32-37 ◽  
Author(s):  
Frederick Jia-Pei Miao ◽  
Tony Jer-Fu Lee
Keyword(s):  
Vasoactive Intestinal Polypeptide ◽  
Arterial Wall ◽  
Immunohistochemical Study ◽  
Picric Acid ◽  
Cerebral Arteries ◽  
Nerve Fibers ◽  
Morphological Data ◽  
Immunohistochemical Method ◽  
Double Labeling ◽  
Functional Interactions

The possible co-localization of choline acetyltransferase (ChAT) and vasoactive intestinal polypeptide (VIP) in the nerve fibers of cat cerebral arteries was examined by a sequential double-labeling immunohistochemical method. Diaminobenzidine and tetramethylbenzidine were used as chromogens to distinguish ChAT (protein) and VIP (peptide) immunoreactivities. Since available fixatives often did not provide simultaneous preservation of optimal protein and peptide immunoreactivities, a new fixative, buffered periodate-paraformal-dehyde-picric acid-formaldehyde-lysine (PPPFL), was formulated and tested. PPPFL fixative is more reliable for simultaneously preserving ChAT and VIP immunoreactivities than were periodate-lysine-paraformaldehyde (PLP) fixative, Zamboni's fixative, or 2% paraformaldehyde solution alone. Using PPPFL as fixative, both ChAT immunoreactive (ChAT-I) and VIP-immunoreactive (VIP-I) fibers in cerebral arteries appeared as bundle and fine fibers. Most ChAT-I and VIP-I fibers were separate. Portions of ChAT-I and VIP-I fibers often ran closely in parallel or across each other. Overlaying of VIP-I on ChAT-I fibers and relay connections between them were also observed. These morphological data suggest the potential functional interactions between cholinergic and VIPergic innervations. In <5% of the fibers examined did ChAT and VIP immunoreactivities appear to be co-localized. These data therefore do not support the hypothesis that acetylcholine and VIP are co-localized in most fibers innervating the cerebral arterial wall.

scholarly journals Anatomical variations of circle of Willis - a cadaveric study

2017 ◽  
Vol 4 (4) ◽  
pp. 1249 ◽  
Author(s):  
Ramanuj Singh ◽  
Ajay Babu Kannabathula ◽  
Himadri Sunam ◽  
Debajani Deka
Keyword(s):  
Cerebral Artery ◽  
Anterior Cerebral Artery ◽  
Anterior Part ◽  
Cerebral Arteries ◽  
Anatomical Variations ◽  
Circle Of Willis ◽  
Anterior Communicating Artery ◽  
Surgical Interventions ◽  
Collateral Channel ◽  
The Right

Background: The circle of Willis (CW) is a vascular network formed at the base of skull in the interpeduncular fossa. Its anterior part is formed by the anterior cerebral artery, from either side. Anterior communicating artery connects the right and left anterior cerebral arteries. Posteriorly, the basilar artery divides into right and left posterior cerebral arteries and each join to ipsilateral internal carotid artery through a posterior communicating artery. Anterior communicating artery and posterior communicating arteries are important component of circle of Willis, acts as collateral channel to stabilize blood flow. In the present study, anatomical variations in the circle of Willis were noted.Methods: 75 apparently normal formalin fixed brain specimens were collected from human cadavers. 55 Normal anatomical pattern and 20 variations of circle of Willis were studied. The Circles of Willis arteries were then colored, photographed, numbered and the abnormalities, if any, were noted.Results: Twenty variations were noted. The most common variation observed is in the anterior communicating artery followed by some other variations like the Posterior communicating arteries, Anterior cerebral artery and posterior cerebral artery (PCA) was found in 20 specimens.Conclusions: Knowledge on of variations in the formation of Circle of Willis, all surgical interventions should be preceded by angiography. Awareness of these anatomical variations is important in the neurovascular procedures.

scholarly journals Cholecystokinin Induces Cerebral Vasodilatation via Presynaptic CCK2 Receptors: New Implications for the Pathophysiology of Panic

2003 ◽  
Vol 23 (3) ◽  
pp. 364-370 ◽  
Author(s):  
Cristina Sánchez–Fernández ◽  
Carmen González ◽  
Linda D. Mercer ◽  
Philip M. Beart ◽  
Mariano Ruiz–Gayo ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Cerebral Arteries ◽  
Neural Mechanism ◽  
Nerve Fibers ◽  
No Synthase ◽  
Neurogenic Vasodilatation ◽  
Whole Mount ◽  
Cerebral Vasodilatation ◽  
First Time ◽  
Cck2 Receptors

The authors report that cholecystokinin (CCK), via its subtype 2 receptor (CCK2R) located presynaptically on cerebral arteries, mediates the release of nitric oxide (NO), which induces vasodilatation. Whereas CCK octapeptide and its fragment CCK tetrapeptide (CCK-4) lack a direct effect on the smooth muscle of pial vessels, the authors showed that both CCK peptides modulate the neurogenic responses in bovine cerebral arteries. The neurogenic vasodilatation induced by CCK-4 was blocked by the CCK2R antagonist, L-365,260, and antagonized by neuronal NO synthase (nNOS) inhibitors, but was independent of the endothelium. In whole-mount arteries, CCK2Rs were detected in nerve fibers and colocalized with nNOS and synaptophysin. The findings provide, for the first time, a neural mechanism by which CCK may increase cerebral blood flow.

scholarly journals Possible Origins and Distribution of Immunoreactive Nitric Oxide Synthase-Containing Nerve Fibers in Cerebral Arteries

1993 ◽  
Vol 13 (1) ◽  
pp. 70-79 ◽  
Author(s):  
Kazuhiko Nozaki ◽  
Michael A. Moskowitz ◽  
Kenneth I. Maynard ◽  
Naoki Koketsu ◽  
Ted M. Dawson ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Nitric Oxide Synthase ◽  
Ganglion Cells ◽  
Cerebral Arteries ◽  
Nerve Fibers ◽  
Circle Of Willis ◽  
Sphenopalatine Ganglion ◽  
Sprague Dawley ◽  
Pial Arteries ◽  
Oxide Synthase

The distribution of perivascular nerve fibers expressing nitric oxide synthase (NOS)-immunoreactivity was examined in Sprague–Dawley and Long–Evans rats using affinity-purified rabbit antisera raised against NOS from rat cerebellum. NOS immunoreactivity was expressed within the endothelium and adventitial nerve fibers in both rat strains. Labeled axons were abundant and dense in the proximal anterior and middle cerebral arteries, but were less numerous in the caudal circle of Willis and in small pial arteries. The sphenopalatine ganglia were the major source of positive fibers in these vessels. Sectioning postganglionic parasympathetic fibers from both sphenopalatine ganglia reduced the density of NOS-immunoreactive (IR) nerve fibers by >75% in the rostral circle of Willis. Moreover, NOS-IR was present in 70–80% of sphenopalatine ganglion cells. Twenty percent of these neurons also contained vasoactive intestinal polypeptide (VlP)-immunoreactivity. By contrast, the superior cervical ganglia did not contain NOS-IR cells. In the trigeminal ganglion, NO-IR neurons were found chiefly within the ophthalmic division; ∼10–15% of neurons were positively labeled. Colocalization with calcitonin gene-related peptide (CGRP) was not observed. Sectioning the major trigeminal branch innervating the circle of Willis decreased positive fibers by ≤25% in the ipsilateral vessels. In the nodose ganglion, 20–30% of neurons contained NOS-immunoreactivity, whereas less than 1% were in the C2 and C3 dorsal root ganglia. Three human circles of Willis obtained at autopsy showed sparse immunoreactive fibers, chiefly within vessels of the posterior circulation. Postmortem delay accounted for some of the reduced density. Our findings indicate that nerve fibers innervating cerebral arteries may serve as a nonendothelial source of the vasodilator nitric oxide (NO). The coexistence of NOS and VIP within sphenopalatine ganglion cells raises the possibility that two vasodilatory agents, one, a highly diffusable short-lived, low-molecular-weight molecule, and the other, a polar 28 amino acid-containing peptide, may serve as coneuromediators within the cerebral circulation.

scholarly journals Association Between The Posterior Part Of The Circle Of Willis And Vertebral Artery Hypoplasia

2019 ◽  
Author(s):  
Virginija Gaigalaite ◽  
Jurate Dementaviciene ◽  
Augenijus Vilimas ◽  
Danute Kalibatiene
Keyword(s):  
Basilar Artery ◽  
Anterior Part ◽  
Posterior Part ◽  
Proximal Part ◽  
Circle Of Willis ◽  
Anterior Circulation ◽  
Vertebrobasilar System ◽  
Vertebral Artery Hypoplasia ◽  
Blood Flow Redistribution ◽  
Made In

AbstractBackgroundIt is not clear whether the configuration of the posterior part of the circle of Willis (CW) depends on the proximal part of the vertebrobasilar system. Our aim is to evaluate the posterior part of CW in association with different size of vertebral arteries (VA) in subjects free from stroke and TIA.Materials and methodsThe present study was based on a sample of 923 subjects free from stroke and TIA who were examined from 2013 through 2018. All the participants underwent MRA examination. The duplex ultrasonographic examination of the extracranial arteries (vertebral and carotid) was performed. VA was defined as hypoplastic (VAH) when VA diameter in the entire course was less than 2.5 mm. We classified the posterior communicating arteries (PCoA) as presence PCoA, absence/hypoplastic PCoA and fetal CW (FCW). The comparison of the posterior part of CW was made in subjects with normal VA and VAH of a different degree (communicating with basilar artery (VAH-BA) and not communicating with the basilar artery and terminating in PICA, neck or aplasia (VAH-PICA)).ResultsFCW was found in 15.9% of subjects, bilaterally – in 2.3 %. The coexisting VAH was more common in subjects with FCW rather than in those with adult CW (respectively, 28.6% and 13.4%, p<0.001). Aplasia of A1 of the anterior cerebral artery, i.e. blood flow redistribution in the anterior part of anterior circulation in the majority of cases (in 6 of 7 cases) was found ipsilaterally to FCW. FCW was recorded in 50% of the subjects with VA - PICA in comparison with 13.5% of those with normal VA and 22.8% with VAH - BA, p<0.005. On the contrary, absence/hypoplasia of both PCoA was mostly found in the group with normal VA in comparison with VAH-BA and VAH-PICA (accordingly, 50.7%, 38.6% and 12.5%, p<0.01).ConclusionIndividuals with VAH have a different pattern of the posterior part of CW in comparison with those with normal VA. With the increasing degree of VAH, the proportion of FCW increases, while the proportion of absence/hypoplastic of both PCoA decreases.

An electrophysiological and anatomical study of projections to the mouse cortical barrelfield and its surroundings

1985 ◽  
Vol 53 (3) ◽  
pp. 686-698 ◽  
Author(s):  
J. C. Nussbaumer ◽  
H. Van der Loos
Keyword(s):  
Anterior Part ◽  
Posterior Part ◽  
Anatomical Study ◽  
Nerve Fibers ◽  
Hair Follicles ◽  
Natural Stimulation ◽  
Whisker Pad ◽  
The Common ◽  
Cortical Map ◽  
Stimulation Of

This study establishes a cortical map of the somatosensory periphery of the mouse head, with emphasis on the whisker pad. Data in the literature on the projection of the common hair follicles are confusing, notably the question whether or not this projection is separated from or overlaps with that of the facial vibrissae, the barrelfield. Microelectrode recordings in the barrelfield and its immediate surroundings upon natural stimulation of the periphery were followed by microlesions and histological reconstruction. Results show that the barrelfield consists of two parts: an anterior part where vibrissal follicles and the skin bearing them are represented, and a posterior part receiving only vibrissa inputs. The skin between these latter vibrissae is represented outside the barrelfield. We conclude that the partially dissociated cortical representation of skin and vibrissae may allow large vibrissae to be used in tasks requiring greater acuity than the shorter ones provide. This hypothesis is supported by the observation that, owing to special muscles, large vibrissae are more mobile than short ones. We also propose that the segregation of inputs from vibrissae and common fur is related to the number of nerve fibers serving one follicle, and we indicate an experimental model to test this possibility.

Microsurgery of the Third Ventricle: Part 1

Neurosurgery ◽  
1981 ◽  
Vol 8 (3) ◽  
pp. 334-356 ◽  
Author(s):  
Isao Yamamoto ◽  
Albert L. Rhoton ◽  
David A. Peace
Keyword(s):  
Lateral Ventricle ◽  
Anterior Part ◽  
Third Ventricle ◽  
Posterior Part ◽  
Posterior Wall ◽  
Pineal Region ◽  
Circle Of Willis ◽  
Cerebral Vein ◽  
Foramen Of Monro ◽  
3Rd Ventricle

Abstract The 3rd ventricle is one of the most surgically inaccessible areas in the brain. It is impossible to reach its cavity without incising some neural structures. Twenty-five cadaveric brains were examined in detail to evaluate the surgically important relationships of the walls of the 3rd ventricle. The routes through which the 3rd ventricle can be reached are: (a) from above, through the foramen of Monro and the roof after entering the lateral ventricle through the corpus callosum or the cerebral cortex; (b) from anterior, through the lamina terminalis; (c) from below, through the floor if it has been stretched by tumor; and (d) from posterior, through the pineal region or from the posterior part of the lateral ventricle through the crus of the fornix. The posterior part of the circle of Willis and the basilar artery are intimately related to the floor, the anterior part of the circle of Willis and the anterior cerebral and anterior communicating arteries are related to the anterior wall, and the posterior cerebral artery supplies the posterior wall. The deep cerebral venous system is intimately related to the 3rd ventricle; the internal cerebral vein is related to the roof, and the basal vein is related to the floor. The junction of these veins with the great vein forms a formidable obstacle to the operative approach to the pineal gland and the posterior part of the 3rd ventricle.

Fine structure of the rectal papillae of the oriental fruuit fly, Dacus dorsalis Hendel (Tephritidae, Diptera Insecta)

1990 ◽  
Vol 48 (3) ◽  
pp. 498-499
Author(s):  
Len Wen-Yung ◽  
Mei-Jung Lin
Keyword(s):  
Fine Structure ◽  
Cell Membrane ◽  
Intercellular Space ◽  
Anterior Part ◽  
Apical Cell ◽  
Posterior Part ◽  
Apical Cell Membrane ◽  
Dacus Dorsalis ◽  
Radial Cell ◽  
Circular Base

Four cone-shaped rectal papillae locate at the anterior part of the rectum in Dacus dorsalis fly. The circular base of the papilla protrudes into the haemolymph (Fig. 1,2) and the rest cone-shaped tip (Fig. 2) inserts in the rectal lumen. The base is surrounded with the cuticle (Fig. 5). The internal structure of the rectal papilla (Fig. 3) comprises of the cortex with the columnar epithelial cells and a rod-shaped medulla. Between them, there is the infundibular space and many trabeculae connect each other. Several tracheae insert into the papilla through the top of the medulla, then run into the cortical epithelium and locate in the intercellular space. The intercellular sinuses distribute in the posterior part of the rectal papilla.The cortex of the base divides into about thirty segments. Between segments there is a radial cell (Fig. 4). Under the cuticle, the apical cell membrane of the cortical epithelium is folded into a regular border of leaflets (Fig. 5).

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