[Increase in GP IIb-IIIa and P2Y12 Receptors in Activated Platelets as the Possible Indicator of de novo Protein Synthesis].

Although platelets lack nuclei, they are capable of de novo protein synthesis. We speculate that key platelet receptors are involved in the regulation of this process, and the changes in their number indicate the de novo protein synthesis in platelets. The object of our study was native platelets obtained from healthy donors. Using flow cytometry and Western blot, we determined the number of GP IIb-IIIa receptors (fibrinogen receptor) and P2Y12 receptors (ADP receptor) on the surface of platelets upon their activation with ADP and collagen. To verify the approaches and techniques used, we studied IL-1ß protein, which was previously shown to be synthesized de novo in activated platelets. GP IIb-IIIa receptor numbers correlate with the number of P2Y12 receptors on the cell surface (R = 0.45, p = 0.03). It was demonstrated that the platelet receptor numbers are higher on the surface of the cells with high functional activity. According to the data obtained by Western blot, upon the cell activation with ADP, the number of GP IIb-IIIa and P2Y12 receptors increases, which may serve as evidence of these proteins being synthesized in the activated platelets. It was observed that the level of P2Y12 and IL-1ß was lower in the samples where GP IIb-IIIa receptor was blocked by the selective inhibitor, i.e., the Fab fragment of the antibodies that specifically recognizes the GP IIb-IIIa complex. This suggests the important role of GP IIb-IIIa receptor in the regulation of protein synthesis.

[THE NEW APPROACH TO EVALUATION OF ENDOTHELIUM DYSFUNCTION: DETECTION OF NUMBER OF CIRCULATING ENDOTHELIUM CELLS USING FLOW CYTOMETRY TECHNIQUE].

The endothelium dysfunction takes leading place in pathogenesis of development of cardiovascular diseases. The circulating endothelium cells of peripheral blood can act as a direct cell marker of damage and remodeling of endothelium. The study was carried out to develop a new approach to diagnose of endothelium dysfunction by force of determination of number of circulating endothelium cells using flow cytometry technique and to apply determination of circulating endothelium cells for evaluation of risk of development of ischemic heart disease in women of young and middle age. The study embraced 62 female patients with angiography confirmed ischemic heart disease, exertional angina pectoris at the level of functional class I-II (mean age 51 ± 6 years) and 49 women without anamnesis of ischemic heart disease (mean age 52 ± 9 years). The occurrence of more than three circulating endothelium cells by 3 x 105 leukocytes in peripheral blood increases relative risk of development of ischemic heart disease up to 4 times in women of young and middle age and risk of development of acute myocardial infarction up to 8 times in women with ischemic heart disease. The study demonstrated possibility to apply flow cytometry technique to quantitatively specify circulating endothelium cells in peripheral blood and forecast risk of development of ischemic heart disease in women of young and middle age depending on level of circulating endothelium cells.

[Gender differences in clinical and hemoreologic disorders in elderly patients with non-cardioembolic ischemic stroke].

Clinical manifestation and platelet homeostasis parameter results in elderly patients with atherothrombotic and lacunar strokes are presented. There is platelet activation in these patients manifested by increasing of P-selectin expression in response to adenosindiphosphate induction on flow-cytometry. Agregometry method was not informative for platelet activity estimation in these patients. Von Willebrand factor receptor expression on the platelet may have prognostic value for acute period. The fibrinogen receptor expression on the platelet was increased in women with stroke comparing with men.

[The molecular mechanisms of platelets activation in patients with cerebrovascular disease].

Cerebrovascular disease is a main cause of mortality and one of the big medical problems. After the vascular wall's damage the endothelial cells secrete the von Willebrand factor which then connects with its platelet's receptor GP Ib-V-IX. There are two polymorphisms Thr145Met and T(-5)C of the GP Iba gene associated with arterial thrombosis development. Also the difference in platelets' genes expressions was shown in patients with various clinical course of ischemic heart disease. The aim of this study was to investigate the role of platelet's receptor for von Willebrand factor in platelets' activation in patients with cerebrovascular disease. 123 patients with cerebrovascular disease and 97 healthy donors were included into the study. We analyzed the level of receptor for von Willebrand factor on platelet's membrane by flow cytometry, Thr145Met and T(-5)C GP Iba polymorphiams by PCR-RFLP, the GP Iba gene expression by RT-PCR and ADP-induced platelet aggregation by Born method. We have shown: 1) the 145Met GP Iba allele prevalence in patients with atherotrombotic stroke development due to macroangiopathy; 2) the pre-mRNA transform into the mature mRNA in activated platelets and this process may be stopped by the antiplatelet therapy by acetylsalicylic acid.