The collagen and elastin content of the arterial wall in the dog

1957 ◽  
Vol 146 (925) ◽  
pp. 541-551 ◽  
Keyword(s):  
Pulmonary Artery ◽  
Thoracic Aorta ◽  
Abdominal Aorta ◽  
Arterial Wall ◽  
Dry Weight ◽  
Arterial Tree ◽  
Thoracic And Abdominal ◽  
Saphenous Artery ◽  
Systemic Arterial Tree ◽  
Made In

A survey has been made in adult dogs of the collagen and elastin content of the walls of arteries varying in size from the thoracic aorta to the saphenous artery. In all arteries, except the smallest, collagen and elastin together formed about 50% of the dry weight. In the smallest the proportion was somewhat higher. On the basis of relative proportions of elastin and collagen the systemic arterial tree was found to be divided rather sharply into two regions: in the intrathoracic aorta there was about twice as much elastin as collagen in the wall; in all other vessels the relation was reversed, there being about twice as much collagen as elastin. The transition between the more elastic intrathoracic aorta and the more collagenous extrathoracic vessels was abrupt and took place over a distance of only 5 cm or so. The pulmonary artery resembled the extrathoracic vessels rather than the thoracic aorta in ratio of elastin to collagen. Newborn and young puppies showed a similar difference to adults between thoracic and abdominal aorta, although we did not investigate the relation between the two vessels in detail.

Arterial mechanics in the fin whale suggest a unique hemodynamic design

1994 ◽  
Vol 267 (3) ◽  
pp. R805-R818 ◽  
Author(s):  
R. E. Shadwick ◽  
J. M. Gosline
Keyword(s):  
Thoracic Aorta ◽  
Arterial Wall ◽  
Carotid Arteries ◽  
Fold Increase ◽  
Arterial Tree ◽  
Balaenoptera Physalus ◽  
Descending Aorta ◽  
Fin Whale ◽  
Internal Radius ◽  
Characteristic Pressure

An analysis of the dimensions of the aortic tree and the mechanical properties of arterial wall tissues in the fin whale (Balaenoptera physalus) is presented. The aortic arch is greatly expanded, having an internal radius at an estimated mean blood pressure (13 kPa) that is 2.5 times greater than that of the descending thoracic aorta. At this pressure, the elastic modulus of the arch wall (0.4 MPa) is 30 times less than that of the descending aorta (12 MPa). Consequently, even though some capacitance is provided anteriorly by the relatively compliant innominate and carotid arteries, > 90% of the arterial capacitance resides in the arch. The characteristic pressure wave velocity (C0) and impedance (Z0) were calculated from vessel dimensions and elasticity. A predicted 20-fold increase in Z0 between the arch and thoracic aorta should provide a major reflecting site, effectively uncoupling the arch from the remainder of the arterial tree. The dimensions of the arch relative to the likely pressure wavelengths within it suggest that it acts like a compliant windkessel that greatly reduces the pulsatility of the inflow to the descending aorta, which itself likely acts as a rigid, tapered manifold. It is suggested that the presence of both a highly compliant arch and a relatively rigid descending aorta is an adaptation for diving.

Regional differences in vasculotoxic effects of cyclosporin in rats

1995 ◽  
Vol 73 (11) ◽  
pp. 1661-1668 ◽  
Author(s):  
Marleen Verbeke ◽  
Leo de Ridder ◽  
Johan Van de Voorde ◽  
Norbert Lameire
Keyword(s):  
Thoracic Aorta ◽  
Abdominal Aorta ◽  
Regional Differences ◽  
Treatment Schedule ◽  
Study Protocols ◽  
Relaxation Responses ◽  
Thoracic And Abdominal ◽  
And Control

Studies on cyclosporin-induced vasculotoxicity often yielded discrepant results, possibly as a result of differences in study protocols. The aim of the present study was to analyse cyclosporin-induced vasculotoxicity in arteries of different size and origin. Therefore, rats were treated with cyclosporin, 20 mg∙kg−1∙day−1, by gastric gavage for 10 days. In our previous studies, this treatment schedule induced renal functional impairment in vivo and an impaired relaxation response of thoracic aortic rings in vitro. Relaxation of various arteries (thoracic and abdominal aorta and carotid, renal, and interlobar arteries) from cyclosporin-treated and control rats in response to endothelium-dependent and -independent vasodilators was analysed. The thoracic aorta showed diminished endothelium-dependent and -independent relaxations; in the abdominal aorta no impairment was observed. Moreover, the dysfunction of the thoracic aorta seemed to be homogeneous along its length and showed an abrupt termination at the level of the diaphragm. In all other segments studied, no impairment of the relaxation responses was found. A similar pattern of vascular damage was found in rats treated with a very toxic cyclosporin treatment (50 mg∙kg−1∙day−1 s.c. × 7 days). The results indicate regional differences in cyclosporin-induced vasculotoxicity. The thoracic aorta, and in view of the fall of the renal blood flow, most likely also the renal resistance vessels, could be more susceptible than other vessels to cyclosporin-induced vascular dysfunction.Key words: cyclosporin, rat, arteries, vasorelaxation.

Increased Prostacyclin Generation in Minipig Vascular Tissue After Atherogenic Diet

1979 ◽  
Author(s):  
H. Sinzinger ◽  
P. Clopath ◽  
K. Silberbauer
Keyword(s):  
Pulmonary Artery ◽  
Abdominal Aorta ◽  
Serum Cholesterol Level ◽  
Vascular Tissue ◽  
Atherogenic Diet ◽  
Tissue Lipid ◽  
Lipid Levels ◽  
Abdominal Aortic ◽  
Synthetic Standard ◽  
Thoracic And Abdominal

The effect of an atherogenic diet on PGI2-generation was studied in 24 miniature pigs fed a diet consisting of 25.6% lard, 2.65% peanut oil, 2.65% cholesterol and 69.1% commercial minipig chow. In all the minipigs the abdominal aortic endothelium was detached with an arterial embolectomy catheter. Prostacyclin generation in the thoracic and abdominal aorta and pulmonary artery was assessed in terms of inhibition of platelet aggregation compared with the effect of a synthetic standard. Blood and tissue lipid levels and the morphology of the arteries and different organs were examined. PGI2-formation was greater in the pulmonary artery, followed by thoracic and abdominal aorta. Balloon catheterization caused a 50% decrease in PGI2-synthesis. PGI2-production increased with ascending blood and tissue lipid levels; at the highest serum cholesterol level (1147 mg%) saturation of PGI2-release by the thoracic aortic segment was observed. In control animals (4) PGI2-generation in thoracic and abdominal aortic segments was 35% lower in the male than in the female pigs.

Consumption of oxygen by thoracic and abdominal aorta of the rat

1963 ◽  
Vol 205 (6) ◽  
pp. 1200-1202 ◽  
Author(s):  
Robert E. Priest
Keyword(s):  
Nitrogen Content ◽  
Thoracic Aorta ◽  
Abdominal Aorta ◽  
Deoxyribonucleic Acid ◽  
Unit Weight ◽  
Liver And Kidney ◽  
The Difference ◽  
Thoracic And Abdominal ◽  
Low Nitrogen

Consumption of oxygen in vitro by thoracic and abdominal aorta and of liver and kidney of rats was measured by direct Warburg manometry and related to the weight of tissue and to the content of nitrogen and of deoxyribonucleic acid (DNA). On the basis of numbers of cells present, as determined by the content of DNA, thoracic aorta respires at a rate one-fifth that of liver. Thoracic aorta respires more actively than abdominal aorta but also contains more nitrogen and more DNA per unit weight than abdominal aorta. The difference in consumption of oxygen between these two segments of aorta can be explained largely, although not entirely, on the basis of numbers of cells present. Because of the lesser content of nitrogen and DNA in abdominal aorta, it must contain larger amounts of some substance which contributes to weight and has a low nitrogen content.

Validation of a patient-specific one-dimensional model of the systemic arterial tree

2011 ◽  
Vol 301 (3) ◽  
pp. H1173-H1182 ◽  
Author(s):  
Philippe Reymond ◽  
Yvette Bohraus ◽  
Fabienne Perren ◽  
Francois Lazeyras ◽  
Nikos Stergiopulos
Keyword(s):  
Arterial Wall ◽  
Specific Model ◽  
Constitutive Law ◽  
Distributed Model ◽  
Patient Specific ◽  
Dimensional Model ◽  
Arterial Tree ◽  
One Dimensional ◽  
Flow Waveforms ◽  
Systemic Arterial Tree

The aim of this study is to develop and validate a patient-specific distributed model of the systemic arterial tree. This model is built using geometric and hemodynamic data measured on a specific person and validated with noninvasive measurements of flow and pressure on the same person, providing thus a patient-specific model and validation. The systemic arterial tree geometry was obtained from MR angiographic measurements. A nonlinear viscoelastic constitutive law for the arterial wall is considered. Arterial wall distensibility is based on literature data and adapted to match the wave propagation velocity of the main arteries of the specific subject, which were estimated by pressure waves traveling time. The intimal shear stress is modeled using the Witzig-Womersley theory. Blood pressure is measured using applanation tonometry and flow rate using transcranial ultrasound and phase-contrast-MRI. The model predicts pressure and flow waveforms in good qualitative and quantitative agreement with the in vivo measurements, in terms of wave shape and specific wave features. Comparison with a generic one-dimensional model shows that the patient-specific model better predicts pressure and flow at specific arterial sites. These results obtained let us conclude that a patient-specific one-dimensional model of the arterial tree is able to predict well pressure and flow waveforms in the main systemic circulation, whereas this is not always the case for a generic one-dimensional model.

A Novel Model of Tobacco Smoke–Mediated Aortic Injury

2021 ◽  
pp. 153857442110630
Author(s):  
Amir F. Azarbal ◽  
Tana Repella ◽  
Eric Carlson ◽  
Elise C. Manalo ◽  
Braden Palanuk ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Thoracic Aorta ◽  
Abdominal Aorta ◽  
Tobacco Smoke ◽  
Inflammatory Cells ◽  
Smoke Exposure ◽  
Tobacco Smoke Exposure ◽  
Osmotic Minipumps ◽  
Thoracic And Abdominal

Objective Tobacco smoke exposure is a major risk factor for aortic aneurysm development. However, the initial aortic response to tobacco smoke, preceding aneurysm formation, is not well understood. We sought to create a model to determine the effect of solubilized tobacco smoke (STS) on the thoracic and abdominal aorta of mice as well as on cultured human aortic smooth muscle cells (HASMCs). Methods Tobacco smoke was solubilized and delivered to mice via implanted osmotic minipumps. Twenty male C57BL/6 mice received STS or vehicle infusion. The descending thoracic, suprarenal abdominal, and infrarenal abdominal segments of the aorta were assessed for elastic lamellar damage, smooth muscle cell phenotype, and infiltration of inflammatory cells. Cultured HASMCs grown in media containing STS were compared to cells grown in standard media in order to verify our in vivo findings. Results Tobacco smoke solution caused significantly more breaks in the elastic lamellae of the thoracic and abdominal aorta compared to control solution ( P< .0001) without inciting an inflammatory infiltrate. Elastin breaks occurred more frequently in the abdominal aorta than the thoracic aorta ( P < .01). Exposure to STS-induced aortic microdissections and downregulation of α-smooth muscle actin (α-SMA) by vascular smooth muscle cells (VSMCs). Treatment of cultured HASMCs with STS confirmed the decrease in α-SMA expression. Conclusion Delivery of STS via osmotic minipumps appears to be a promising model for investigating the early aortic response to tobacco smoke exposure. The initial effect of tobacco smoke exposure on the aorta is elastic lamellar damage and downregulation of (α-SMA) expression by VSMCs. Elastic lamellar damage occurs more frequently in the abdominal aorta than the thoracic aorta and does not seem to be mediated by the presence of macrophages or other inflammatory cells.

Medial elastin in the thoracic and abdominal aorta of sheep and lambs

1983 ◽  
Vol 61 (2) ◽  
pp. 115-119 ◽  
Author(s):  
Charles van Baardwijk ◽  
Margot R. Roach
Keyword(s):  
Thoracic Aorta ◽  
Abdominal Aorta ◽  
Cross Sections ◽  
Abrupt Change ◽  
Pulse Wave ◽  
Local Stress ◽  
Linear Increase ◽  
Stress Concentrations ◽  
Abrupt Increase ◽  
Thoracic And Abdominal

Aortas were removed from six mature lambs and four sheep and pressure fixed at 100 and 120 mmHg pressure (1 mmHg = 133.322 Pa), respectively, in 10% buffered formalin. The numbers of elastin layers were counted from cross sections at different distances down the aorta, from the distal arch to the iliac bifurcation, and showed a linear decrease in the thoracic aorta. In the abdominal aorta there was no difference in values from the diaphragm to the aortoiliac bifurcation in the lamb, but a slight decrease in the sheep. If y = mx + b, where y is the number of medial lamellar units (MLU), b the intercept, x the distance from the last brachiocephalic branch in centimetres, and m the slope, we obtained the following equations (with standard deviations): lamb thoracic aorta; y = −6.29 (±0.71)x + 106 (±12); sheep thoracic aorta; y = −3.46 (±0.40)x + 140 (±21.4); lamb abdominal aorta; y = 0.51 (±1.48)x + 37 (±7.7); sheep abdominal aorta; y = −0.85 (±0.28)x + 66 (±5.9). Tension per lamellar unit was calculated and plotted versus distance yielding a linear increase in the entire lamb aorta but an abrupt increase between thoracic and abdominal aortas in the sheep. This causes the pulse wave to move uniformly with increasing speed along the length of the lamb aorta but would cause an abrupt change in the wave at or about the diaphragm in the sheep. Distortions in the pulse wave could produce local stress concentrations in the abdominal aorta which might render it more susceptible to atherosclerosis than the thoracic aorta.

Diffusional support of arteries

1985 ◽  
Vol 248 (6) ◽  
pp. H901-H906 ◽  
Author(s):  
A. H. Werber ◽  
D. D. Heistad
Keyword(s):  
Thoracic Aorta ◽  
Abdominal Aorta ◽  
Nutritional Support ◽  
Vasa Vasorum ◽  
Relative Role ◽  
Arterial Lumen ◽  
Aortic Media ◽  
The Media ◽  
Thoracic And Abdominal

The relative role of the arterial lumen, adventitial vasa vasorum, and medial vasa vasorum in nutritional support of arteries is unclear. We have used a newly developed autoradiographic method to study diffusion of metabolically inert [14C]antipyrine into arteries to determine the relative importance of different pathways in nutritional support of arteries. [14C]antipyrine was homogenously distributed across the media of small arteries within 15 s, which indicates that diffusion into the central media was rapid. In the thoracic and abdominal aorta, levels of antipyrine were higher in the inner media (P less than 0.05) than in the middle of the media. Levels of antipyrine in outer media of the thoracic aorta (which has medial and adventitial vasa) were comparable to those observed in the inner media, but antipyrine levels were lower in outer than in inner media of the abdominal aorta (which has adventitial vasa only). Ligation of intercostal arteries, which are the source of medial vasa vasorum in the thoracic aorta, decreased diffusional support to the outer media of the thoracic aorta. We conclude that 1) diffusional support is more effective in thinner muscular arteries than in the aorta, 2) both luminal and abluminal sources of nutrition are important, particularly for the aorta, 3) vasa vasorum appear to be important for adequate diffusional support of the thoracic aortic media, and 4) medial vasa vasorum may be more effective than adventitial vasa vasorum in nourishing the aorta.

Abstract 397: Regional Differences in Periaortic Adipose Tissue

2016 ◽  
Vol 119 (suppl_1) ◽  
Author(s):  
Khanh-Van Tran ◽  
Timothy Fitzgibbons ◽  
Silvia Corvera
Keyword(s):  
Adipose Tissue ◽  
Thoracic Aorta ◽  
Abdominal Aorta ◽  
Aortic Ring ◽  
Valuable Insight ◽  
Mrna Levels ◽  
Brown Adipocytes ◽  
Pparγ Agonist ◽  
Brown Adipose ◽  
Thoracic And Abdominal

Introduction: To combat obesity and associated comorbidities, it is vital to have an in-depth understanding of the adipose tissue. The presence of brown adipose tissue is associated with decrease risk of T2DM while the opposite is true for the presence of visceral white adipose tissue. In this study, we examined the adipocyte populations surrounding the thoracic and abdominal aorta of C57Bl/6J mice. Methods: We utilized the aortic ring assay to examine the adipocytes arising from the thoracic and abdominal regions of the aorta. We previously found that adipocyte progenitors proliferate when tissue is embedded in Matrigel. C57Bl/6J mice were sacrificed, thoracic and abdominal aorta fragments were removed, embedded in Matrigel matrix and allowed to proliferate in the absence or in the presence of Rosiglitazone, a PPARγ agonist. Explants were then fixed in formaldehyde for immunofluorescence analysis or used for RNA extraction and subsequently real-time PCR. Results: Classically, cells that arise from the aorta fragments are spindle-like and express several endothelial cell markers, such as CD31, CD34 and vWF. We found that in the presence of rosiglitazone, cells arising from the aorta accumulate lipid droplets to take on an adipocyte phenotype. In the presence of rosiglitazone, the expression of CD31 and CD34 are decreased and expressions of adiponectin and perilipin are increased. The perilipin staining patterns in these cells are consistent with that of adipocytes, i.e. surrounding a lipid droplet. Adipocytes around the abdominal aorta have higher mRNA levels of Hoxc9, a homeobox gene expressed higher in white adipocytes than brown adipocytes. Conversely, adipocytes arising from the thoracic aorta have higher expression of UCP-1 and cidea, markers of brown adipocytes. Conclusion: Results show that adipocytes from thoracic and abdominal regions of the aorta have different genotypes and phenotypes. Cells surrounding the thoracic aorta may have more of a “beige,” in between white and brown phenotype, as opposed to a classic white adipocyte phenotype seen in fat cells surrounding the abdominal aorta. Our e x vivo aortic ring model is a tool that can provide valuable insight into the role that adipocytes play in different regions of the aorta.

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