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Biomedical subjects

J Larrue

Publications and source records attributed to J Larrue.

At least 73 records · Page 4Linked to original sources
PubMed1980

[Biosynthesis in vitro of extracellular matrix in arteriosclerotic areas of rabbit aortas. Autoradiographic study of tritiated proline incorporation kinetics].

The elaboration of the extracellular matrix was investigated by radio-autoradiography after incubation of aortic strips, isolated from thoracic aortas of healthy and atherosclerotic rabbits, with tritium labeled proline. Time course experiments indicated that there was a delay of about one hour before significant amounts (25%) of tritiated macromolecules were released from the intact smooth muscle cells. On the contrary, both, the level of incorporation and the rate of excretion of macromolecular components by modified smooth muscle cells of the atherosclerotic area from injured strips were increased. The results indicate that, under the conditions of incubation in vitro, the modified smooth muscle cells of atherosclerotic plaque exhibit a particular behaviour for both, quantitative and qualitative features of macro-molecular synthesis of the extracellular matrix.

Animals↗
PubMed1977

Fibrous long spacing collagen in aortic explants of normal rabbit cultured in hypercholesterolemic serum.

Aortic tissues consisting of all three tunics were removed from normal adult rabbits and cultured in a semisynthetic gelosed medium supplemented by 10% serum obtained either from normal or hypercholesterolemic rabbits. Fibrillar cross-striated aggregates appeared with a high frequency (50%) in the extracellular space of explants cultured from four to eight days in medium supplemented by serum from hypercholesterolemic rabbits, but did not appear in explants cultured in serum from control animals (3%). The electron-dense segment was ruthenium red positive and digested by testicular hyaluronidase. The electron-lucent segment, composed of ruthenium red negative thin filaments, was not modified after hyaluronidase treatment but was strongly digested after collagenase treatment. It is believed that this material was fibrous long spacing collagen synthetized under culture conditions, as shown after tritiated proline incorporation.

Animals↗
PubMed1977

Effects of hypercholesterolaemic serum on aortic explants from normal rats.

Aortic explants obtained from normal adult rats and composed of all 3 tunics were cultured in a semi-synthetic gelosed medium supplemented by 10% serum. Explants cultured with normocholesterolaemic serum kept their in vivo characteristics for more than 12 days at electron microscope and histometabolic levels. However, explants showed considerable differences when cultured in a medium with hypercholesterolaemic serum. Cell proliferation in the tunica media and enhanced synthesis of macromolecular components of the extracellular matrix were observed. These laterations occurring inside the explants, which had kept all their tissular relationships, suggest that this culture system may be valuable for further studies on atherosclerotic processes.

Animals↗
PubMed1976

[Influence of a lathyric agent and of hypercholesterolemic serum on cell cultures of fetal rabbit aorta].

Cell cultures of foetal rabbit aorta are cultivated with a lathyric agent (beta-amino-propio-nitrile) or with an hypercholesterolemic serum; if morphological features, in these two cases, correspond with modifications observed, in vivo, when adult rabbits are respectively submitted to the same treatment, enzymatic activities of collagen metabolism vary in opposite way. Therefore, the influence of different parameters to be studied on vascular cell functions become easier.

Aminopropionitrile↗
PubMed1976

[Study of the extracellular macromolecular meshwork elaborated by rat aortic cells in secondary culture].

Rat aortic smooth muscle cells isolated by digestion of the vessels by elastase and trypsin and grown in subculture, are examinated by phase, optic and electron microscopy for their ability to synthesize connective tissue components. Large amounts of extracellular material accumulates within the spaces between the cell; it consists of amorphous substance identified histochemically as elastin, of 110 A microfibrils and of periodic fibrils (430-490 A); the chemical nature of these two last components is discussed.

Animals↗
PubMed1975

Estimation of seric and parietal inhibiting power of elastase; its changes with experimental conditions.

The existence of a parietal elastase and its physiological role in the pathology of the arterial wall remain unknown: it is probably difficult to demonstrate its specific activity because of existing tissular inhibitors, homologus to seric inhibitors. The change of seric inhibitor power when elastase is injected to animals with or without a cholesterol diet is discussed. Moreover, an aortic inhibiting power against elastase is shown. Our results emphasize some new aspects of elastase in its role in arterial wall pathology.

Animals↗
PubMed1975

[Experimental rat deciduoma: histoenzymology].

The modifications of enzymatics activities which involved dehydrogenases (LDH, MDH and G6PDH) alkalines phosphatases (Ph. Alc., ATP/as at Ph 7,2 and Ph 9,4) and hydrolases (Ph Ac. and beta Glu) were studied during the experimental deciduomata evolution in the Rat from the 5th to the 9th day. One the 5th day the uterus were used as control. Dehydrogenases and alkalines phosphatases activites appeared in isolated cells of sub-epithelial and middle antimesometrial stroma on the 5th day. Then, on the 6th day, they distributed themselves in strings of 8 to 10 cells. On the 7th day, they were regulary arranged in the decidual area. The growing decidual tissue was always surrounded by an hydrolysis activity.

Acid Phosphatase↗
PubMed1975

[Ultrastructural study of secondary cultures of rat aorta. Cellular aspects].

Cells obtained from the media and intima of ten days rat aorta, after enzymatic dissociation, were grown in subculture for up to three months. Electron microscopic observations demonstrate that these cells maintained the morphology of smooth muscle cells at all phases of their growth in subculture and kept their ability to synthesize and secrete intracellular proteins with better enzymatic features than the cells obtained by proliferation at the periphery of an explant.

Animals↗
PubMed1975

[Enzyme alterations of the arterial wall following the combination of a lathyrogenic treatment and of moderate hypercholesterolemia in the young rabbit].

To determinate the part of humoural and parietal factors in atherosclerotic injury genesis, metabolism alteration study is realised on aortic cell wall of rabbits which are submitted to a chronical lathyritic intoxication alone, or simultaneously or alternatively associated with a cholesterolemic diet. Catabolic activity increase of beta-glucuronidase occurs in hypercholesterolemic rabbits. Beta-aminoproprionitrile, lathyrogenic drug used, stimulates biosynthetic pathways: increase of soluble proteins, energetic enzyme activities (lacticodeshydrogenase, malicodeshydrogenase), conjonctival protein metabolism (procollagen lysyl hydroxylase); in the same time, cell wall disturbances and lipidic deposits are facilitate when rabbits are submitted to cholesterolemic diet.

Aminopropionitrile↗