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Ross Fiziol Zh Im I M Sechenova ; 91(1): 46-52, 2005 Jan.
Artigo em Russo | MEDLINE | ID: mdl-15773579


Influence of a high-molecular compound capable of augmenting viscosity, namely: polyethylene oxide Polyox WSR-301, on hemodynamic parameters in rat mesenteric microvessels was investigated. A substantial decrease in the arteriolar hemodynamic resistance caused by the polymer was revealed. Special research has shown that this reaction is not connected with a vasodilatation and, therefore, is caused by a reduction in the "apparent" viscosity of the blood, i.e., it is a consequence of changed properties of the blood flow.

Viscosidade Sanguínea/efeitos dos fármacos , Intestinos/irrigação sanguínea , Polietilenoglicóis/farmacologia , Animais , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Hemorreologia , Masculino , Artérias Mesentéricas/fisiologia , Veias Mesentéricas/fisiologia , Microcirculação/efeitos dos fármacos , Ratos , Ratos Wistar , Resistência Vascular/efeitos dos fármacos
Aviakosm Ekolog Med ; 32(1): 77-9, 1998.
Artigo em Russo | MEDLINE | ID: mdl-9606520


High-molecular polymers apt to directly influence flow microstructure were tested as a fundamentally new method for correcting microhemodynamics in microgravity. Pressure in the mesenteric arterial microvessels was measured two weeks in rats adapted to the head-down suspension. Intravenous polyethylene oxide (Polyox WSR-301, end-concentration in the order of 2.10(-7) g/ml), reduced the microvascular pressure by 26%, whereas in the control pressure was reduced by only 15%. Systemic arterial pressure showed an equal drop in the groups (by 10 to 11%). These results suggest that the biomechanical agent weakens resistance to the blood flow in the body region where blood supply is impaired by microgravity.

Adaptação Psicológica , Hipotensão Ortostática , Artérias Mesentéricas/efeitos dos fármacos , Polietilenoglicóis/farmacologia , Polímeros/farmacologia , Animais , Hemodinâmica/efeitos dos fármacos , Ratos , Fatores de Tempo , Ausência de Peso
Usp Fiziol Nauk ; 26(2): 31-43, 1995.
Artigo em Russo | MEDLINE | ID: mdl-7785309


An analysis of the hemodynamic consequences of the injections of long linear polymers with high molecular weight is introduced. These injections lead to an increase of the cardiac output, to a decrease of the blood pressure, and hence cause a reduction of the resistance to blood flow. It follows that such kind of polymers is able to normalize hemodynamics under some pathophysiological conditions, e.g., during experimental atherosclerosis, ischemic state, hemorrhagic shock. An addition of drag-reducing polymers into the blood system is associated with a modification of the blood flow microstructure itself.

Circulação Sanguínea/efeitos dos fármacos , Polímeros/farmacologia , Animais , Circulação Sanguínea/fisiologia , Hemodinâmica/efeitos dos fármacos , Hemodinâmica/fisiologia , Peso Molecular , Polímeros/uso terapêutico
Biull Eksp Biol Med ; 116(11): 552-5, 1993 Nov.
Artigo em Russo | MEDLINE | ID: mdl-8312561


The infusion of polyethylene oxide in anesthetised rats in a total dose of 10(-7) g/ml caused a 10-16% reduction in blood pressure. This injection has been associated with 17% decreased pressure (servo-nulling method) and 54% increased blood velocity (laser Doppler fluxmetry) in mesenteric arterioles (d - about 24 mu), but no increase in their internal diameter was observed (image-split method). Vasodilatation (adenosine, 10(-5) M) did not change the hemodynamic response of the arterioles to polymer infusion. These results suggest that microdisturbances of blood flow which can be diminished by drug-reducing polymers are more important for the vascular resistance to blood than it has been previously.

Artérias Mesentéricas/efeitos dos fármacos , Polietilenoglicóis/farmacologia , Resistência Vascular/efeitos dos fármacos , Animais , Arteríolas/efeitos dos fármacos , Arteríolas/fisiologia , Fenômenos Biofísicos , Biofísica , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Masculino , Artérias Mesentéricas/fisiologia , Ratos , Ratos Wistar