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The effect of some local anesthetics on conductance of bilayer lipid membranes made of egg yolk lecithin has been studied. Low concentrations of anesthetics were shown to gradually increase the integral conductance of bilayers. This effect is connected with the protonophore activity of the tested anesthetics and it caused the stabilization of the bilayers. High concentrations of anesthetics caused destabilization of membranes and formed zones of nonselective increased conductance.

The pyrene eximerization, polarity of pyrene microenvironment and relaxation times (T1 and T2) of water protons in the systems of monolamellar egg yolk lecithin liposomes were investigated depending on temperature and bilayer modification by cholesterol and alpha-tocopherol. The thermotropic transition of pyrene eximerization degree at 38 degrees C, abrupt polarity change of pyrene microenvironment at 22-25 degrees C in modified by tocopherol liposomes and abnormal behaviour of water proton relaxation times in the temperature range of 39-40 degrees C were found. This high-temperature transition is supposed to be due to the structural alteration in the region of egg yolk lecithin heads.

The effect of cyclic decapeptide of gramicidin S on electrical conductivity of bilayer lipid membranes has been studied. The integral conductivity of bilayer has been shown to increase with the growth of antibiotic concentration. The integral conductivity increase occurs as series of conductivity discrete leaps, differing in amplitude from fluctuations of conductivity caused by linear gramicidins. In the series of selectivity of bilayer membranes for cations of alkaline metals the rubidium ion is before the cesium ion. This is the only difference between this series and the series of relative ionic mobility series of cations of alkaline metals in water solutions.