[The molecular mechanism of the antiviral action of 2-(1'-aminoethyl)-bicyclo (2.2.1) heptane hydrochloride]. / Issledovanie molekuliarnogo mekhanizma protivovirusnogo deistviia 2-(1'-aminoétil)-bitsiklo (2.2.1) geptan gidrokhlorida.

The interaction of 2-(1'-aminoethyl)-bicyclo (2.2.1) heptane hydrochloride possessing anti-influenza activity with flat bilayer lipid membranes was studied. The compound was shown to adsorb and build-in into the lipid bilayer changing the charge, modulus of transverse elasticity, and ion permeability of the membranes. Pre-addition of the preparation into the medium washing the membrane prevents interaction of influenza virus matrix protein with the membrane. The compound also destroys M-protein aggregates in the aqueous phase. The possible role of the observed effect of the compound in its antiviral action is discussed.

Interaction of the antivirus agents remantadine and amantadine with lipid membranes and the influence on the curvature of human red cells.

Surface potential difference, conductance, and elasticity changes of bilayer lipid membranes induced by the antivirus drugs amantadine and remantadine were measured. An influence on the human erythrocyte shape was shown. Both drugs are stomatocytogenic. The adsorption at the cytoplasmatic membrane was electrophoretically proved. The heat-induced vesiculation is partly inhibited. No microvesicles were observed. Instead, large tails which did not detach from the cell body were seen. The general conclusion is that these amphiphilic adamantane derivatives are membrane agents which modify membrane interaction processes, possibly by influencing the bending properties.

[Interaction between plasma lipoproteins and bilayer lipid membranes. The role of surface charge]. / Vzaimodeistvie lipoproteidov plazmy s bisloinymi lipidnymi membranami. Rol' poverkhnostnogo zariada.

Interactions of planar BLM with different thickness and surface charge were analysed theoretically. Drawing together of the membranes is accompanied with the appearance of intramembrane potential jumps which may cause destruction and breakdown of the membranes. The theory is extrapolated to the interaction between spherical lipoprotein particles and planar BLM. Experimentally calculated (by means of ESR) surface charges of lipoproteins of low density (LLD) (--0,3 . 10(-2) C/m2) and lipoproteins of high density (LHD) (--2 . 10(-2) C/m2) enabled calculation of the interaction energy between the particles and BLM as well as of the values of intramembrane potential jumps. The latter cause local reconstructions of the membranes in the contact region and fusion of the particles with them. The earlier obtained experimental data were proved by the finding that LHD adsorption as compared with LLD is impeded due to the existence of a high energetic barrier. These peculiarities of the particles manifested during their interactions with BLM seem to be one of the factors responsible for atherogenic function of LLD and antiatherogenic one of LHD.

[Peculiarities of interactions of bilayer lipid membranes with human plasma lipoproteins from patients with ischemic heart disease]. / Osobennosti vzaimodeistviia s BLM lipoproteidov, vydelennykh iz plazmy liudei s ishemicheskoi bolezn'iu serdtsa.

It is shown that the modifying ability sequence of human plasma lipoproteins from patients with ischemic heart disease (IHD) in respect to BLM made of oxidized cholesterol is [HDL2] less than [LDL] less than [VLDL] less than [HDL3] and differs from that in healthy people which is [VLDL], [LDL] less than [HDL2] less than [HDL3]. It is suggested that changes in lipid-protein compositions of the lipoproteins in the case of IHD determined the alterations of the nonreceptor interactions of the atherogenic and antiatherogenic lipoprotein classes with the cell membranes.

[Plasma lipoproteins, modifiers of the ionic permeability of artificial lipid membranes]. / Lipoproteidy plazmy krovi--modifikatory ionnoi provodimosti iskusstvennykh lipidnykh membran.

With the help of BLM a possibility of non-receptor interaction between the blood plasma lipoproteides and isolated apoproteins immediately with the lipid part of plasmic membranes was shown. Incorporation of lipoproteides in BLM is of a cooperative character and induces cationic permeability in them. Specific interactions with the membranes of aterogenic and antiaterogenic classes of lipoproteides, the role of dimensions and surface charge of lipoproteide particles and of apoproteins and calcium ions in the course of incorporation are revealed. It is suggested that asymmetrical incorporation of a lipoproteide particle in the bilayer and a local increase of the membrane permeability for calcium results in the activation of the contractile system of the cortical layer and in the formation of endocytosis vacuole transporting the lipoproteide particles into the cell.

[Effect of human plasma lipoproteins on ionic conductivity of lipid bilayer membranes]. / Vliianie lipoproteidov plazmy krovi cheloveka na ionnuiu provodimost' bisloinykh lipidnykh membran.

An interaction was studied between various lipoproteins (low density lipoproteins--LDL, very low density lipoproteins--LVDL, subfractions of high density lipoproteins--HDL2, HDL3) and artificial bilayer lipid membranes (BLM) produced from oxydized cholesterol. The lipoproteins increased from 100 to 1000-fold the conductivity of BLM for cations Na+, K+, Ca2+, but not for anions. Critical concentrations of the lipoproteins at which their modifying effect was manifested, correlated reciprocally with the size of the lipoprotein particles; they were arranged as follows: VLDL < LDL < HDL2 < HDL3. Decrease in the pH value lowered these critical concentrations. Addition of Ca2+ into the solution decreased the critical concentrations of VLDL and LDL from 2- to 4-fold as well as of HDL2 and HDL3--from 9- to 12-fold. The electrostatic power appears to be important in interaction between the lipoproteins and bilayer lipid membranes.