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The parameters describing the structural and functional state of membranes depending on the level of reduced glutathione in erythrocytes were studied. It was shown, that the decrease in the concentration of reduced intracellular glutathione in erythrocytes upon metabolic depletion (prolonged incubation of cells at 37 degrees C in the absence of glucose) or a rapid irreversible depletion of glutathione with 1-chloro-2,4-dinitrobenzene enhances lipid peroxidation processes in membranes, inhibits the membrane-bound NAD.H methemoglobin reductase activity and decreases the intensity of 1,6-diphenyl-1,3,5-hexatrien fluorescence. The data obtained suggest that the depletion of reduced intracellular glutathione causes changes in the physicochemical state of the erythrocyte membrane: the accumulation of lipid peroxidation products, changes in the physical state of lipid bilayer and the inhibition of membrane-bound NAD.H-methemoglobin reductase activity.

The relationship between the parameters (percentage and rate) of hemolysis by sodium dodecyl sulfate and the time of incubation of human erythrocyte suspensions in glucose-free medium at 37 degrees C was studied. The polyphasic changes in the parameters were found, which depend on the mode of pretreatment: ATP depletion by iodoacetate, heat denaturation of spectrin, and treatment of cells by valinomycin. It was found that the percentage and rate of detergent hemolysis do not always change in parallel.

It is shown that the oxidation of membrane protein SH-groups of human erythrocytes by diamide leads to the intensification of vesiculation and the formation on the cell surface of "senescent antigens". These processes were studied during prolonged incubation of erythrocytes at 37 degrees C in the absence of glucose. It was found that the formation of vesicules in ATP-depleted cells correlated with the appearance of "senescent antigens" (r = 0.9, p0.01). The oxidation of protein SH-groups takes place at the early stages of vesiculation and strengthening of autologous immunoglobulin binding, indicating that the oxidation of the other groups of membrane proteins plays the leading role in the modification of surface properties.

It is shown that the value of activation energy of red blood cells autohemolysis in temperature range of 4 + 37 degrees C is considerably smaller than that at t37 degrees C and is about 50 kJ/mol in isotonic saline buffer, pH 7.4. This means that the change of limiting stage of hemolysis occurs at 37 degrees C. It is found that the decreasing of oxygen partial pressure in the medium resulted in marked inhibition of hemolysis without alteration of activation energy in temperature range of 20 divided by 37 degrees C and on the contrary in intensification of hemolysis at t20 degrees C. It is concluded that oxidative processes are essential in autohemolysis in temperature range of 20 divided by 37 degrees C and the oxygen stabilizes the structure state of erythrocytes below 20 degrees C.

The influence of different factors modifying erythrocyte membrane structure on the value of power index of doze dependence of photohemolysis of hematoporphyrin-sensitized erythrocytes has been investigated. It has been established that thermoinduced spectrin aggregation results in increase the index, whereas vesiculation under metabolic exhaustion of erythrocytes greatly decreases value n. A more considerable decrease of the parameter was observed when photohemolysis of erythrocytes was occurred in alkaline medium. It has been shown that the observed decrease of the power index in the latter case is not caused by pH-induced changes of photochemical reactions but by some dark processes. The decrease is possibly brought about by pH-induced conformational changes of protein band 3.

Hemin hemolysis of human erythrocytes at 37 degrees C has been investigated by the kinetic method. It has been observed that hemin affects erythrocytes by two mechanisms, inducing "quick" and "slow" hemolysis. The "quick" hemolysis is completed after the first few minutes. The final level of "quick" hemolysis is a function of relative hemin concentration. It is equal to zero when the latter is smaller than the minimum concentration Cmin = 10(8) molecules of added hemin per cell. The final level of "slow" hemolysis is always 100%. It is suggested that the limiting step of autohemolysis is the membrane proteins oxidation catalyzed by endogenous hemin originating from methaemoglobin during erythrocyte incubation at 37 degrees C.

The activation energies of three processes (AT-depended vesiculation, release of potassium ions from erythrocytes and formation of methemoglobin) in erythrocytes incubated in phosphate buffer are measured in the range 4-37 degrees C. It is show that the Arrhenius plots for the first two processes have the same characteristics namely break at temperature around 18 degrees C, and Ea-58 kJ/mol at t18 degrees C. These data suggest that the velocity of ATP-depended vesiculation of erythrocytes is determined by the membrane permeability to monovalent cations. The appearance of methemoglobin in extracellular medium is characterized by a distinct value Ea(120 kJ/mol), although kinetics of this process is similar to vesiculation kinetics. Connection between considered processes and interrelation between ATP-depended vesiculation and spontaneous vesiculation are discussed.

Dose dependencies of the rate of hematoporphyrin sensitized photolysis of erythrocytes and leucocytes have been investigated. It has been shown that power index of dose dependency for erythrocytes equal 2, while for leucocytes it lies between 1 and 2, suggesting heterogeneity of total leucocyte fraction in photosensitivity.

Erythrocyte vesiculation and changes in membrane protein composition during storage of blood and red cell concentrates in solution "Glugicir" at 4 +/- 2 degrees C have been studied. It is shown that the main part of vesicles is shedding after 9 days of storage. This process corresponds to a decrease of protein 3 and to polyphase changes of membrane-bound hemoglobin as is shown by gel-electrophoresis. During 9-day storage, when erythrocyte ATP is constant and the vesicle shedding is small, an increase in membrane-bound hemoglobin and a decrease of spectrin in isolated membranes take place. The above changes are not the result of oxidative processes in membrane lipid bilayer or in hemoglobin. There was also protein destruction in membranes of stored erythrocytes. It is suggested that in stored blood two type of erythrocyte vesiculation take place: one is due to cell senescence, the other results from metabolic depletion.

It is shown that during sensitized by haematoporphyrin photooxidation accumulation of TBA-active products in destroyed cells (human erythrocytes, rat thymocytes, pig leucocytes) occurs considerably faster than in the intact ones. Similar acceleration is observed in intact erythrocytes after the amount of reduced glutathione in it was decreased. It is supposed that the cause of intensification processes of lipid peroxidation consists in separation of the antioxidant system from the plasma membrane.

Erythrocyte vesiculation, kinetic parameters of tryptophane phosphorescence at room temperature and activity of erythrocyte membrane during storage of human blood at 4 +/- 2 C were studied. It is shown that before the erythrocyte vesiculation stage (10-15 days of storage) two types of changes in the structural state of the membrane proteins occur: 1) on the 1-5th days and 2) on the 5-10th days of blood storage.

The effect of temperature on the activities of cytoplasmic and membrane-bound fractions of NADH-cytochrome beta 5 reductase on the total activity of methemoglobin reductase in intact human erythrocytes was studied within the temperature range of 20-50 degrees C. The above three activities showed a break in the Arrhenius plots at 42 degrees C which was attributed to irreversible inactivation of the enzymes. Thermal inactivation of methemoglobin reductase in erythrocytes was found to increase the methemoglobin content concomitantly with a decrease in the osmotic stability and activation of spontaneous cell hemolysis.

The spectro-fluorescent characteristics of synovial exudate in different diseases of the knee joint were studied. It was established that in pigmented villonodular synovitis the position of the maximum of fluorescence spectrum of synovial exudate was in the range of 510-530 nm and in synovitis of other etiology 430-440 nm. The authors propose a method of differential diagnosis of pigmented villonodular synovitis by fluorescent parameters of synovial exudate.

Effect of antibody to peripheral protein spectrin and antibody to integral protein of band 3 on kinetic parameters of pyruvate and glucose transport in the pink erythrocyte ghosts has been studied. It is shown that spectrin structure reorganization induced by the antibody to this protein has different effect on pyruvate and glucose transport parameters. Band 3 protein modification with the help of the antibody to this protein changes pyruvate transport parameters, while glucose transport is not changed. The data obtained show that facilitated diffusion of glucose and anions in the erythrocyte membrane is carried out by different carriers, the action of these carriers essentially depending on the structure state of spectrin.

The fluorescence of intensivity of membrane-bound diphenylhexatriene (DFHT) of erythrocytes of the cancer patients is found to increase as compared to that of donors. No reliable differences are detected in a degree of fluorescence polarization of DFHT and pyren excimerization in erythrocyte membranes of cancer patients and donors. The data obtained show that under the development of malignant tumours the structure state of lipid bilayer of erythrocyte membrane does not undergo significant changes. However an increase of the fluorescence intensivity of the membrane-bound DFHT, evidently, is the result of changes in protein-lipid interactions in the membrane.

Effects of depletion and resynthesis of intracellular ATP on the properties of human erythrocytes (deformability, osmotic fragility) and on the structural parameters of their membranes (U. V. fluorescence spectra, protein aggregation) were studied. Incubation of the erythrocytes in the absence of glucose at 37 degrees C was shown to result in a number of consequent alterations: crenating and decrease in deformability of erythrocyte cells--a change in relative contents of membrane proteins--aggregation of membrane proteins and reversible shift of their fluorescence spectra. The evidence is considered in favour of the spectra shift due to dephosphorylation of membrane proteins.

Binding of tetrasulfophenylporphyn with human serum albumin was studied by spectral methods. The presence on the protein of one centre of porphyrin binding with high affinity was shown.

A number of breaks were recorded on the curve of Arrhenius relationship of the rate constant of the dye 1-anilino-8-naphthalenesulphonate sodium salt (ANS) input into human erythrocytes of 20, 28, 36, 42 and 46 degrees C. Variations in the values of activation energies within the temperature range of 28-36 degrees and 42-46 degrees C obtained in various blood samples allow to consider these temperatures as those at which structural changes of the membranes take place. The values of activation energy of the process for temperature "conformers" of the erythrocyte membrane are 12(10-20 degrees C), 26.5 (20-28 degrees C), 34.2(36-42 degrees C) and 47 kcal/mol (t is greater than 46 degrees C). Within the temperature range of 28-36 degrees and 42-46 degrees C an irreversible decrease of permeability to ANS of the erythrocyte ghost after their incubation for 10 min at increased temperatures were observed. Thus the temperature regions of the change in erythrocyte permeability correspond to those at which the resealing of ghost takes place. The break in Arrhenius graph at 20 degrees C seems to characterize a highly cooperative "point" transition. The lipid nature of the initiator of structural transition within 28-36 degrees C is proved by a sharp increase of the permeability of liposomes prepared from erythrocyte membrane lipids to ANS at 28 degrees C. The nature of the initiators of two other thermal transitions is discussed.

Glucose transport was determined by oxygen adsorption in solution when glucose was oxidized with glucoseoxidase, injected into erythrocyte ghosts. Temperature dependence of glucose transport velocity shows a break at 20 degrees C, which was described in literature. Small concentrations of chlorpromazine (about 2-10(-5) M) somewhat activates the transport but does not changes its temperature dependence. Higher concentrations of anaesthetics (beginning with 1-10(-4) M) inhibit the transport, decrease the temperature of break and increase the activation energyies of the process both lower and higher of the transition temperature. The change of working velocity of glucose carrier under the action of anaesthetic and temperature is accounted for by structural reconstructions in lipids, which are heterogeneously distributed along the erythrocyte membrane plane.

The ability of a positively charged local anesthetic dibucain introduced into cell suspension prior to its irradiation to accelerate porphyrin-sensitized photodestruction of different cells is shown. Neutral anesthetics benzocain and ethanol had no such effect. There has been obtained evidence that the dibucain-induced increase in the amount of cell-bound sensitizer plays an essential role in the acceleration of photodestruction.

Changes in the acetylcholinesterase activity, thermal and osmotic stability of erythrocyte membranes of the cancer patients are found as compared with this activity of erythrocyte membranes of donors. No differences were detected in the rate of phosphate anion transfer through the erythrocyte membranes in the examined persons. The data obtained show that the development of malignant tumours is followed by the changes in the structural and functional state of surface components of erythrocyte membranes.

Temperature transitions of spectrin in solution and in human erythrocyte membranes are recorded in the region t greater than 40 degrees C by irreversible changes in protein fluorescence spectra. Structural changes are completed 20 min after the sample incubation at an increased temperature. Both for isolated spectrin and for erythrocyte ghosts the temperature of half-transition is 46 +/- 1 degree C. There is no transition in the membranes after the removal of spectrin. Transitions in erythrocyte ghosts and in spectrin solution disappear at pH 5 when spectrin is in an aggregated state. Spectrin is suggested to be responsible for the transitions at 50 degrees C; its state in the cells areas more thermostable than in isolated membranes.

Thermohemolysis kinetic curves of erythrocytes in the temperature interval of 37-75 degrees C in different media and in the course of blood storage were studied. Mechanism of thermohemolysis is proposed. The rate constants of hemolysis stages are introduced. It is shown that these parameters are sensitive to the changes of structural state of erythrocytes.

Mediated agglutination of erythrocytes was studied in the presence of concanavalin A (Con A). Agglutinability of erythrocytes from cancer patients was found to be higher than that of normal cells as a result of chemical factors present in the blood plasma which transform the cell surface, the number of Con A receptors remaining unchanged. It is concluded that increased agglutinability of erythrocytes from cancer patients is mainly due to a decrease in the negative charge of cells and the appearance of echinocytic forms.

The paper discusses a physico-chemical method for cancer diagnosis by evaluating fluorescence intensity of blood serum in ultraviolet and visible spectra excited by 313-317 nm wavelength monochromatic light. The procedure elicited as much diagnostic evidence as blood-CEA level determination but proved much cheaper, more time-saving and causing less discomfort to the patient. The reliability, sensitivity and specificity of the method in diagnosis of tumors of various histogenesis and site are discussed.

Measurements were carried out of the rate constants of erythrocyte thermohemolysis and hemoglobin thermoaggregation in various animal species and also for the man under the action of hemoglobin-modifying factors (CO2, O2, ethanol). It is concluded from the obtained correlation dependences that hemoglobin thermodenaturation initiates erythrocyte thermohemolysis. The identity of the early stages of erythrocyte thermohemolysis and aging is suggested.