[Change of current-voltage characteristics of amphotericin B ion channels accompanying its incorporation into the membrane]. / Izmenenie bol't-ampernoi kharakteristiki ionnykh kanalov amfoteritsina B pri ego vstraivanii v membranu.

Non-linearity of amphotericin B current-voltage characteristics is determined by means of the third harmonic generated in the membrane. A change of the sign of non-linearity is revealed during incorporation of antibiotic molecules into a membrane, i. e. the incorporation is not a simple increase of the number of similar ionic channels in the membrane.

[Study of the volt-ampere characteristics of ion channels by transmembrane current harmonics]. / Izuchenie vol't-ampernykh kharakteristik ionnykh kanalov po garmonikam transmembrannogo toka.

A method is proposed for measuring the coefficient of non--linearity beta of current--voltage characteristics of the class i (U) approximately U (1 + beta U2) of ionic channels formed by grammicidine A (Gra) and amphotericine B by the 3rd harmonics of the membrane current. For Gra A beta depends on the concentration of electrolyte c increasing lg c from -17 B-2 at 0.03 M to 8 B-2 at 3.4 M KCl turning to 0 at c0 = 0.3 divided by 1 M. The membranes of egg lecithin and glycerylmonooleate (GMO) differ in c0 value. Substitution of K+ ion for Li+, of the membrane solvent (n-heptane for n-hexadecane) and freezing of the GMO membrane do not affect beta.

[Elastic properties of lipid bilayer membranes during incorporation of plasma lipoproteins]. / Izmenenie uprugikh svoistv bisloinykh lipidnykh membran pri vstraivanii lipoproteidov plazmy krovi.

Interaction between lipoproteins of very low density /LPVLD/ with bilayer lipid membranes was studied in blood plasma of healthy rabbits and in rabbits with alimentary hyperlipoproteinemia. The LPVLD of healthy animals did not produce any alterations in elasticity and volume of bilayer lipid membranes within 120 sec, whereas the lipid fraction from animals with hyperlipoproteinemia altered these physical properties of the membranes at the period studied. The factors, which are responsible for the action of LPVLD on the bilayer lipid membranes, were both composition and structure of lipoprotein particles. The importance of nitial parameters of the membrane structure in its interaction with lipoproteins was shown using the model system.

[Electrostriction properties of the plasma membrane of the lower epidermis of the bulb of bulb onions]. / Elektrostriktsionnye svoistva plazmaticheskoi membrany kletok nizhnego épidermisa lukovitsy repchatogo luka.

Electrostriction properties of onion bulb epidermis plasma membrane were investigated in a wide frequency range 40 Hz divided by 2kHz and alternative voltage magnitude 140 mV divided by divided by 700 mV. Dynamic Young's modulus [E perpendicular] in direction normal to the membrane surface and loss angle were measured; strong [E perpendicular] and phi dependences on frequency were demonstrated. [E perpendicular] rises as the frequency increases and reached 10(8)-10(9) Pa like BLM prepared from egg lectin-n-hexadecane solution. In the temperature range of 19-30 degrees C [E perpendicular] does not vary more than 20%. The values phi approximately 60 degrees are obtained for different preparations in the whole frequency range. A correlation between electrostriction properties and the physiological state of preparation is marked.

[Changes in the elastic properties of lipid bilayers as a result of different procedures]. / Izmenenie uprugikh svoistv lipidnykh bisloev pri razlichnykh vozdeistviiakh.

The bilayer elasticity modulus approximately E perpendicular is sensitive to alternative electrical field, addition of different detergents and proteins incorporation. The detergents modify the value E1APPROXIMATELY E perpendicular] several times, the kinetics of this effect is more frequently biphasic and its shape and time parameters are characterized with a considerable dispersion; in general the [approximately E perpendicular] value increase for soft membranes and decrease for the membranes and high elasticity modulus. The proteins incorporation as well as the destruction of the membrane is accompanied with the general structure transition of the whole membrane. The measurement of the elasticity modulus is an effective test of protein incorporation in bilayers.

[Assessment of the viscoelastic properties of biological membranes by measurements on bilayers]. / Otsenka viazkouprugikh svoistv biologicheskikh membran po izmereniiam na bisloiakh.

The frequency characteristic of the complex Young modulus along the normal to surface is measured for the bilayer lipid membranes (BLM). For egg lecithin membranes the absolute value of the modulus (formula: see text) rises from 4.10(6) to 10(8) dyn/cm2 (n-decane) and from 10(8) to 10(9) dyn/cm2 (n-hexadecane) with the frequency change from 20 Hz to 15 000 Hz depending on different membrane solvents. (formula: see text) also rises several times if cholesterol is added or lipid hydrocarbon chains are longer or more saturated. If the solvent--n-hexadecane is freezed out in the region of 14 degrees C,(formula: see text) increases up to 10(10) dyn/cm2. The loss angle is measured and real and imaginary parts of (formula: see text) are determined. (formula: see text) posesses the relaxtion times spectrum in the range 10(-5)--10(-3) s. The conclusion is made that biological membranes like BLM have polymer properties, their (formula: see text) values may achieve 10(10) dyn/cm2 and the relaxation times are greater than 10(-3) s.

[Size of the "distortion" area of the membrane close to the ion channel formed by gramicidin A]. / O razmere oblasti "iskazhenii" membrany vblizi ionnogo kanala, obrazovannogo gramitsidinom A.

Young's modolus of the bilayer membrane (BLM) in the direction normal to membrane plane approximately E perpendicular changes if gramicidin A molecules are incorporated into BLM. The plot of approximately E perpendicular on membrane conductivity is a monotonic curve with saturation at BLM conductivity corresponding distances between gramicidin A dimers about 1000 angstrom. The conclusion is made that dimer formation generates drastic reorganization of BLM structure, the size of distortion zone of the membrane near the ionic channel is of the same value.