Magnesium,zinc, and manganese in atherosclerosis of the aorta

Atomic absorption spectrometry was used in a quantitative study of zinc, magnesium, and manganese on 71 postmortal human aortas. Samples were obtained from accident victims 35-65 years of age. Fibrous plaques had higher levels of all three elements when compared to normal aortic tissue. The difference was significant for zinc (p less than 0.001) and magnesium (p less than 0.01). The high elemental levels may be both a cause and effect of atherosclerosis or the result of another unknown parameter.     

Isolation, characterisation, growth and culture of endothelial cells from the rat aorta

Rat aortic endothelial cells have been isolated by the explantation technique and grown in culture. They have been identified morphologically using standard staining techniques, biochemically by identification of angiotensin convertase and have been positively stained for Factor VIII-related antigen by immunofluorescence using both anti-human and anti-rat Factor VIII antibodies. The explantation technique is a successful alternative to enzyme digestion which is not applicable to rat aortic endothelial cells because of the nature of their attachment to the subendothelial layer.     

Sympathetic innervation of the pulmonary artery,ascending aorta,and coronar glomera of the rabbit

Summary Adrenergic nerve fibres were demonstrated in the connective tissue of the rabbit coronar glomera by means of the formaldehyde-induced fluorescence technique for catecholamines. This type of innervation is similar to the adrenergic nerve supply to the rabbit and cat carotid body. Adrenergic fibres terminate subendothelially and only a few can be traced to type I cells in the glomera coronaria. The sympathetic innervation of the ascending aorta is exceedingly sparse in contrast to the pulmonary trunk, while vasa vasorum of the ascending aorta exhibit a dense sympathetic innervation.     

Mechanical analysis of heterogeneous, atherosclerotic human aorta.

An experimental technique was developed to determine the finite strain field in heterogeneous, diseased human aortic cross sections at physiologic pressures in vitro. Also, the distributions within the cross sections of four histologic features (disease-free zones, lipid accumulations, fibrous intimal tissue, and regions of calcification) were quantified using light microscopic morphometry. A model incorporating heterogeneous, plane stress finite elements coupled the experimental and histologic data. Tissue constituent mechanical properties were determined through an optimization strategy, and the distributions of stress and strain energy in the diseased vascular wall were calculated. Results show that the constituents of atherosclerotic lesions exhibit large differences in their bilinear mechanical properties. The distributions of stress and strain energy in the diseased vascular wall are strongly influenced by both lesion structure and composition. These results suggest that accounting for heterogeneities in the mechanical analysis of atherosclerotic arterial tissue is critical to establishing links between lesion morphology and the susceptibility of plaque to mechanical disruption in vivo.     

The wall of the chick embryo aorta harbours M-CFC, G-CFC, GM-CFC and BFU-E

In the 3- to 4-day avian embryo, after the first wave of haemopoiesis which derives in the yolk sac from haemopoietic stem cells formed in situ, haemopoietic cells emerge in an intraembryonic site, the wall of the aorta. In this paper, we demonstrate that this site harbours M-CFC, G-CFC, GM-CFC and late and early BFU-E. In serum-free medium, the growth of M-CFC and GM-CFC was strictly dependent on CSF present in fibroblast-conditioned medium (FCM). The growth of G-CFC was improved when FCM was replaced by a minute quantity of chicken and fetal calf serum. Like erythroid progenitors from bone marrow, BFU-E detected here required anaemic chicken serum to differentiate into haemoglobinized cells. The frequency of the different types of haemopoietic progenitors in the aortic population was very high: 80 M-CFC, 25 G-CFC, 4 GM-CFC and 70 BFU-E for 12,500 aorta cells, i.e. two to eight times more frequent than in the bone marrow population, depending on the type of progenitors.     

Visco-elastic characteristics of the rat aorta

In order to estimate wave propagation "in vitro", aortic compliance has been studied by means of rings and stripes from 6 adult male Wistar rats. Lengthening and shortening maneuvres have been performed; the pulse transmission rate was evaluated by calculating the elastic modulus during the maneuvres. A Norepinephrine infusion has been done. Results obtained show that transmission rate is higher in shortening than in lengthening phases. Norepinephrine did not significantly affect the values. The rate values were not greatly different whether "in vitro" or "in vivo". By increasing specimen stress, the rate too was increased, but the amount was lower than "in vivo" values. Hence it was assumable that rate variations "in vivo", should be partially influenced by elastic modulus, and a vegetative intervention should be implied.     

Proteolipid and human aorta calcification, in vitro

The objective of this study was to determine whether in vitro calcification of human aorta is proteolipid dependent. Homogenates were prepared from tissue with no gross pathologic manifestations. Samples were examined for calcifiability in a metastable calcium phosphate solution before and after lipid extraction. Fractions of the extracted lipid were similarly examined. The tissue calcified before but not after lipid extraction. Calcifiability was restricted to the proteolipid portion of the lipid extract. Under the conditions employed, therefore, proteolipid is required for calcification of human aorta, in vitro.