Joint action of protein-chondroitin-4-keratan-sulfate and hyaluronic acid on erythrocyte aggregation and adhesion]

It was shown that the rate and the degree of erythrocytes aggregation brought about by a mixture of protein-chondroitin-4-keratan sulfate (PCKS) and hyaluronic acid (HA) was greater than the sum of the values of the corresponding indices observed during separate independent action of these proteoglycans on the aggregation of the mentioned cells concentrations as in the mixtures. It may be supposed that such phenomenon is connected with formation in the mixture of a hybrid PCKS-HA complex which is more active in respect to the erythrocyte aggregation than its components separately.     

Monoaminergic innervation of the kidney of the carp (Cyprinus carpio L.)

By means of fluorescent-histochemical method distribution of monoaminergic structures has been studied in the sympatho-adrenal system of the carp (Cyprinus carpio L.) mesonephros. Catecholaminergic nervous fibers are revealed in the walls of adrenal and venous vessels and glomerular arterioles. In the glomerular capillaries they are not found. In the walls of the venous vessels, besides catecholamine-containing nervous fibers, chromaffin cells with long processes running along the vessel are observed. Some contacts of catecholamine-containing structures of the mesonephric vascular wall with the proximal and, very seldom, with distal parts of the nephron canaliculi are demonstrated. Structures containing indolamines are not revealed.     

Effect of homologous immunoglobulin with normal anti-tissue antibodies on the development of strontium-90-induced osteosarcomas in rats

In experiments on Wistar rats it was shown that homologous immunoglobulin (a single dose of 25 mg/kg), with normal antitissue antibodies, subcutaneously injected in the following manner: a single injection 90 days or 6 months, or double injection 3 and 6 months after intraperitoneal administration of strontium 90 (11.1 kBq/kg) reduces osteosarcoma occurrence and increases the average lifetime of animals.     

Protective effect of alpha-tocopherol on the Ca2+-transport system of the sarcoplasmic reticulum membranes in hypercholesterolemia

The effect of antioxidant--alpha-tocopherol--on Ca2+-transporting system in sarcoplasmic reticulum (SR) of the rabbit skeletal muscles was studied in hypercholesterolemia (HC). alpha-tocopherol administration to animals with HC produced a break on the curve of temperature dependence of Ca-ATPase activity at about 20 degrees C, that disappeared in HC, increased the rate of "rapid" SH-group binding by thiol reagents, and normalized the level of unsaturated fatty acids in SR membranes without altering phospholipid content. It is suggested that the damage of Ca-ATPase in HC is mainly due to activation of lipid peroxidation.     

Isolation and characterization of a large,neurite-associated glycoconjugate from neuroblastoma cells

A high molecular weight glycoconjugate has been isolated from neurite-producing neuronal tumor cells in culture and has been designated as I(0) based on its elution characteristics in gel filtration chromatography. This molecule cannot be found in a variety of nonneuronal cells. I(0) is found in the substratum-attached material or cell fraction of neurite-producing neuroblastoma cells, depending upon culture conditions. It is found in the substratum-bound fraction of B104 rat neuroblastoma cells during serum starvation and in the EGTA-detached cell fraction of B104 cells grown in chemically defined N2 medium. It occurs only in the cell fraction of the human neuroblastoma line Platt. Examination of behavioral variants of the B104 rat line further strengthens the association of I(0) with neurite production; the constitutive neurite-producing E(R)B9 variant contains I(0) while the non-neurite-producing E(R)A11 variant does not. I(0) is large, eluting in the void volume of sepharose-CL2B columns. Radioiodination of intact cells with lactoperoxidase shows I(0) to be a cell surface component. Metabolic radiolabeling studies show that it contains a high proportion of polysaccharide to protein, does not contain mannose, and is unsulfated. Alkaline borohydride reduction release two size classes of large polysaccharide chain. The alkaline reduction results, along with the mannose incorporation studies, show the presence of O-glycosidic linkages and few, if any, N-linkages. Resistance to nitrous acid deamination, insensitivity to glycosaminoglycan lyases, and the absence of sulfation, indicate that I(0) does not contain the glycosaminoglycans hyaluronic acid, chondroitin-, dermatan-, or heparin- sulfates. Affinity column chromatography reveals high binding affinity of I(0) to polyornithine and no binding to gelatin (collagen) or the glycosaminoglycans hyaluronate and heparin. These studies describe a unique high molecular weight glycoconjugate on the surface of neurite-producing neuroblastoma cell lines from two species.