PubMed Health⌕ Search

Biomedical subjects

A S Kuznetsov

Publications and source records attributed to A S Kuznetsov.

At least 55 records · Page 3Linked to original sources
PubMed1989

[Structural analysis of the interaction of low density lipoproteins with arterial intima cells in atherosclerosis].

Structural characteristics of low density lipoprotein (LDL)-intimal cellular element interaction were studied in atherosclerotic lesions in the aortas obtained from rabbit with experimentally induced hypercholesterolemia and in human coronary arteries. An electron microscopic autoradiographic examination using 125I to study the in vivo interaction between LDL and rabbit aortic intimal cells indicated that the formation of foam cells was associated with activated endocyte activity and uncontrolled capture of atherogenic lipoproteins. The structural analysis of the interaction of native and modified LDL labelled with colloid gold, on the one hand, and human coronary intimal cells, on the other, was made by using ultrathin sections. This enabled the localization of the receptors to lipoproteins to be established. This also demonstrated that transformation of the cells to foam ones was due to the functional insufficiency of lysosomal activity and to the filling of the cytoplasm with membranelles and membrane-surrounded lipid vacuoles.

Animals↗
PubMed1989

[Modification of blood plasma lipoproteins by a lipid peroxidation product--hexanal].

HDL treated with hexanal is shown to lose the ability for the cholesterol absorption. In the case of LDL at low concentration of the modifying agent the rate of their elimination from the blood stream of the rabbit decrease, but their uptake by the rat macrophages do not differ from the uptake of native lipoproteins. At high concentration of hexanal the rate of the elimination of LDL from the blood stream increases considerably and is close to that of acetylated LDL. Thus, the modification of plasma lipoproteins with monoaldehydes occurring in the aorta wall leads to the loss of the functional properties of the lipoprotein particles.

Aldehydes↗
PubMed1985

[Molecular organization of glutamate-sensitive chemoexcitable membranes of nerve cells. Function of glutamate-binding proteins of the central nervous system when incorporated into liposomes].

The functioning of the glutamate-binding protein of rat brain cortex synaptic membranes was studied by its incorporation into liposomes. The optimal conditions for the receptor protein incorporation were established and the kinetics of 22Na+ and 86Rb+ incorporation into the liposomes in the presence of L-glutamate were analyzed. Modelling of the CNS glutamate receptor functions was found to be dependent on the lipid composition and amount of the incorporated membrane protein. The selective transport of 22Na+ into the liposomes was stimulated in the presence of 10(-4) M glutamate. Addition of monoclonal antibodies against glutamate-binding proteins blocked the incorporation of Na+ into the liposomes. The experimental results are suggestive of the nativity of the liposome-incorporated membrane protein, which is capable of binding glutamate and regulating selective transport of Na+. It was assumed that the glutamate receptor macromolecule represents an integral complex made up of several low molecular weight subunits of glucoprotein nature that form a selective ionic channel.

Animals↗
PubMed1983

[Role of the monocytes and IgG in the development of atherosclerotic lesions in the aorta of rabbits].

In experimental hypercholesterinemia in rabbits, immune autoradiographic studies showed that lesions in the endothelial monolayer of the aorta developed in parallel with IgG deposition in the cytoplasm of the affected endothelial cells and in different parts of atherosclerotic plaques. This process was accompanied by active replacement of blood monocytes into the internal sheath of the aorta in the zone of IgG deposition which appeared to be due to the presence in these cells of Fc-receptors for immunoglobulins. Incomplete catabolism of lipids in the cytoplasm of macrophages of monocytic genesis is one of the key events of atherosclerosis morphogenesis.

Animals↗
PubMed1983

[Apolipoprotein B of plasma lipoproteins incorporated in liposomes: immunological properties and organ distribution when administered to rabbits].

Apolipoprotein B (apo B) isolated from low density lipoproteins (LDL) was built in phospholipid-cholesterol liposomes, with the lipid/protein ratio being equal to 33:1. Such liposomes preserved their integrity, whereas the constituent apo B retained its antigenic properties. After intravenous injection to rabbits the pattern of apo B liposome distribution among organs was similar to that of LDL. Apo B liposomes may be used for goal-oriented transport of some substances to organs and tissues whose cells have specific receptors for apo B-containing lipoproteins.

Animals↗
PubMed1983

[Spatial organization of low density lipoproteins of the human aorta (study using fluorescent probes)].

Low density lipids of the atherosclerosis-unaffected human aorta, unlike plasma lipoproteins belonging to the same class, contain lipid peroxidation products in the superficial layer. The viscosity of the lipid phase of the aorta and blood plasma is the same. In protein of aorta lipoproteins, tryptophan residues are outside the particle whereas in plasma lipoproteins, they are buried deep in the lipid phase. The data on energy transfer to the probes provide evidence in favour of the fact that in aorta lipoproteins, protein is lying on the particle surface in a thicker layer and occupies a 2-times lesser area than in plasma lipoproteins.

Adult↗
PubMed1983

[Changes in the size and properties of lipoprotein particles in the extracellular medium during incubation of low density lipoproteins with human fibroblasts].

Electron microscopy, disc electrophoresis in polyacrylamide gel, and microzonal electrophoresis on acetate cellulose were used to examine the changes in the properties of low density lipoproteins (LDL) in extracellular medium during incubation with human fibroblasts. It was established that as a result of LDL interaction with fibroblasts there appeared lipoprotein particles less in size, with higher aggregation ability and electrophoretic mobility. The data obtained indicate that LDL undergo physicochemical changes due to non-specific interaction with fibroblasts.

Cells, Cultured↗
PubMed1980

[Dissociation of low-density lipoprotein complexes with glycosaminoglycans isolated from the human aorta].

It is established that low-density lipoproteins (LDLP) are present in the human vascular wall in the form of complexes with glycosaminoglycans. These complexes dissociate in an electric field and in salt solutions which are usually used for isolating lipoproteins by ultracentrifugation. Besides, in distinction from blood plasma LDL, the LDL of the vascular wall are characterized by a higher flotation rate and asymmetric distribution according to the flotation rate.

Aorta↗
PubMed1980

[Lipoproteins of the vascular wall: complex formation with glycosaminoglycans and interaction with foam cells].

Atherogenic lipoproteins are present in the aortic wall in complexes with various glycosaminoglycans. Reduced uptake of 125I-lipoproteins of low density by the foam cells and diminished respiration-stimulating effect of low-density lipoproteins on the cells under the influence of glycosaminoglycans reflects the capacity of glycosaminoglycans for changing the physico-chemical properties of lipoproteins in the direction of a decrease in their interaction with the foam cells.

Absorption↗
PubMed1977

[Aspects of the clinical use of methoxyflurane analgesia and of the determination of its concentration and distribution in the body].

As a supplement to local anesthesia in aortography, appendectomies and operations for hernia in 118 patients the authors employed through a mask an inhalation anesthetic methoxyflurane in subnorcotic concentrations. The patients were in the state of consciousness, analgesia was adequate, no complications relative to methoxyflurane inhalation were noted inhalation anesthesia with methoxyflurane proved to be safe and effective in combination with local anesthesia. The method is indicated in aortographies.

Analgesia↗
PubMed1976

[Role of foam cells in lipoprotein transformation within the vascular wall].

Foam cells were isolated from atherosclerotic aortas of rabbits following their intima incubation with collagenase and elastase. The viability of the cells, their incidence and nativity were supported histochemically and electron-microscopically. The interaction of the foam cells with lipoproteins was studied in vitro with perfusions of isolated atherosclerotic aortas of rabbits during 6 hours with a medium containing beta- and pre-beta-lipoproteins labelled with I125 or simultaneously with I125 and C14-cholesterol. It was found that after the perfusion the foam cells contain a much higher proportion of radioactivity of the total lipids, cholesterol and cholesterol esters, to that of the proteins, than the perfusate. The foam cells must selectively "capture" the lipids from the lipoprotein particles. The proportion "free cholesterol/cholesterol esters" (according to the radioactivity) proved to be much higher in the foam cells than in the perfusate. The possible mechanisms of the participation of the foam cells in the metabolism of lipoproteins and in the pathogenesis of atherosclerosis are discussed.

Animals↗