digitonin and Arteriosclerosis

The process of cholesterol extraction from the blood of rabbits with experimental atherosclerosis was investigated, with the following reinjection of the blood with reduced amount of cholesterol. Liquid membranes were applied to extract free cholesterol. Emulsion consisting of blood-compatible membrane (oil and sorbitan oleate) and the inner phase (water solution of digitonin) was used as an extractant. The average degree of cholesterol extraction was 23.4%. Pretreatment of the emulsion, its composition and the way of preparation make it possible to perform the extraction from the blood without a considerable increase in the degree of hemolysis.

Topics: Animals; Arteriosclerosis; Blood Transfusion, Autologous; Buffers; Cholesterol; Digitonin; Emulsions; Hexoses; Membranes, Artificial; Methods; Mineral Oil; Rabbits; Time Factors

A digitonin-containing affinity sorbent was prepared using a hydrophilic polymer carrier. The correlation was found between the polymer structure and crosslink. King degree, on the one hand, and the sorbent capacity to bind cholesterol, protein and lipoproteins--on the other. The sorbent was demonstrated to extract predominantly atherogenic lipoproteins from blood plasma.

Topics: Animals; Apolipoproteins; Arteriosclerosis; Cholesterol; Cholesterol, LDL; Cholesterol, VLDL; Digitonin; Hemoperfusion; Humans; Hypercholesterolemia; Lipoproteins, VLDL; Maleic Anhydrides; Polymers; Pyrrolidinones; Rabbits

Topics: Animals; Aorta; Arteriosclerosis; Digitonin; Endothelium; Female; Fibrinogen; Iodine Radioisotopes; Macromolecular Substances; Rabbits; Radionuclide Imaging; Serum Albumin; Serum Albumin, Radio-Iodinated; Sodium Pertechnetate Tc 99m; Technetium; Technetium Tc 99m Aggregated Albumin; Time Factors

The subcellular sites of accumulation of cholesterol and cholesteryl esters in rabbit atheromatous cells, were investigated by morphologic and biochemical techniques. Electron microscopy of lipid-filled cells in situ in atheromatous aortas of cholesterol-fed rabbits revealed lipid accumulation in the cytoplasm as lipid droplets and within lysosomes in the form of lipid globules, membranous whorls, and crystals. When such cells were isolated from the rabbit aortas by enzymic digestion, and then treated with Flickinger's aldehyde fixative containing 0.2 per cent digitonin, characteristic digitonide-lipid complexes ("spicules") were observed in discrete sites of the cytoplasm distinct from the cytoplasmic droplets. If these cells were first stained cytochemically for acid phosphatase and then treated with digitonin-aldehyde fixative, enzyme reaction product was found associated with the spicules indicating that the lysosomes of the atheromatous cells possess digitonin-reactive lipid. Subcellular fractionation of isolated rabbit aortic foam cells by sucrose density gradient centrifugation demonstrated the coequilibration of most of the intracellular unesterified cholesterol with low density lysosomes. Some cholesteryl ester was also associated with low density lysosomes, although most was found in a lipid droplet fraction of very low density. Together the results indicate that in rabbit atheromatous cells, lysosomes are the site of accumulation of intracellular cholesterol in excess of that structurally associated with membranes and that both cytoplasmic droplets and lysosomes are depot sites for cholesteryl esters.

Topics: Acid Phosphatase; Animals; Aorta; Arteriosclerosis; Cholesterol; Cholesterol Esters; Cholesterol, Dietary; Cytoplasm; Digitonin; Female; Lysosomes; Rabbits

Topics: Aged; Aldehydes; Aorta; Arteriosclerosis; Cholesterol; Digitalis Glycosides; Digitonin; Female; Humans; Inclusion Bodies; Microscopy, Electron; Staining and Labeling