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The effects of several forms of plasminogen on the state of actin cytoskeleton of human platelets were studied. A ratio between various actin pools, which were detected by immunoblotting, was taken as indicator of platelet cytoskeleton reorganization. It was revealed that intact platelets contain globular (G) actin and membrane cortex (MC) actin in amounts that are 56 and 40% of filamentous (F) actin level, respectively. In both thrombin- and collagen-activated platelets, actin is almost entirely presented in F-form. Incubation of resting platelets with Lys-plasminogen causes elevation of MC-actin level up to 79% in respect to F-form content. In addition, Lys-plasminogen inhibits reorganization of actin cytoskeleton typical for activated platelets. In contrast to Lys-form, Glu-plasminogen affects neither platelet aggregation nor redistribution of actin pools. Thus, these data indicate that cytoskeletal structures of platelets are involved in realization of anti-aggregating effects of Lys-plasminogen.

A probable increase of the level of calcium-binding protein S100b and soluble form of glial fibrillary acidic protein (GFAP), as well as reducing the level of filament GFAP in the brain of Wistar rats under hepatic encephalopathy development caused by chronic hepatitis (HP) were shown. Increasing concentrations of S100b may stimulate the disassembly of intermediate filaments of astrocytes. The immunohistochemical analysis helps to reveal that astrocytes in the brain of rats that had HP lose the characteristic stellate shape and swelling. Immunoblotting result have shown the fragmentation of the main filament form of GFAP and appearance of low mass derivates. Application of 2-oxoglutarate (2.28 g/l of drinking water during 10 days after the onset of chronic hepatitis) stabilized the studied proteins and the state of astroglia.

The effects of hyperthyreosis on oxidative stress, state of glial intermediate filaments and memory were investigated. We observed a significant increase in lipid peroxidation products into both hippocampus and cortex and memory worsening. The changes of GFAP polypeptides was observed in hippocampus and cortex. In group of rats with hyperthyreosis, the content of GFAP in both soluble and filamentous fractions was increased in hippocampus. This data shows, that glial cytoskeleton is reconstructed under thyroid hormone effects.

The research has shown substantial changes in the percentage correlation between plasmatic membrane proteins and erythrocyte cytoskeleton (alpha-spectrin, beta-spectrin, ankyrin, band 4.1) under type 1 diabetes mellitus. It has also established the difference in the content of erythrocyte membrane glycoproteins, i.e. band 3 proteins and glycophorine A, in healthy donors and patients with diabetes. Thus the content of glycophorine A decreased by 27%, while the content of band 3 protein increased by 23%. Under the pathology, changes in the structure of carbohydrate determinants of erythrocytes membrane glycoproteins were revealed by means of the lectin blot analysis. Type 1 diabetes mellitus is accompanied by an increase in the number of glycoproteins with mannose-containing carbohydrate determinants complementary to Con A and LCA, on the one hand, and a decrease in the number of glycoproteins with sialo- and galactose-containing oligosaccharides complementary to WGA and RCA lectins, on the other hand, on the erythrocyte membrane surface.

Protein composition of mammalian erythrocyte membrane-cytoskeletal complex under the influence of cryoprotectants and freezing-thawing process was studied by the methods of electrophoresis. No quantitative and qualitative differences in the research objects on basic structural proteins in all experimental variants were revealed. Slight changes in cryopreservation process were noted in bovine erythrocytes, where there was a reduction of protein band 6. This may be related to either cryostability of protein or insufficient sensitivity of the method.

Platelets from healthy donors and insuline dependent patients with type 1 diabetes mellitus were examined for proteins specifically interacting in vitro with GST-fused constitutively active (Val12) forms of small GTPases of Rac, Rho and Cdc42. Differential changes in pattern of proteins which bind to these G-proteins in diabetic platelets have been revealed. Obtained results suggest that signalling pathways mediated by Rho GTPases are altered under type I diabetes mellitus. Such changes of actin cytoskeleton regulation may contribute to the higher level of platelet aggregation, which prove to be the etiological background of the late diabetes complications.