[Morpho-biophysical research of erythrocytes of intact and vagotomized rats in various terms after the acute hemorrhage].

The acute massive hemorrhage (35-37% of the blood volume) at rats is accompanied by changes of morphological (diameter, the area, polarizations, the form-factor, integrated and specific absorbency) and biophysical (a relief of a surface and microviscosity of a lipid phase of plasmolemma) characteristics of erythrocytes. Thus character and dynamics of response of erythron initially intact and vagotomized (14 days after operation) animals essentially differ: the former demonstrate significant changes in 3-10 h and 240 h and the latter--in 0.5 h and 96 h.

[Lipid-proteinic interaction in erythrocytie and placental membranes in women with insulin resistance].

Disturbances of erythrocyte and placental membrane functiond have been studied in placenta of pregnant women with obesity and diabetes mellitus type 2. The results of this study demonstrate significant metabolic impairments in women with insulin resistance. Changes in lipid spectrum of erythrocyte membranes and decreased activity of antioxidant enzymes obviously contribute to the development of fetoplacental insufficiency.

Relationships between erythrocyte membrane properties and components of metabolic syndrome in women.

Background: Membrane structure in metabolic syndrome has not been fully investigated. The aim of our study was to determine the relationship between structural parameters of the erythrocyte membrane and blood pressure, indices of obesity, plasma lipids, and glucose levels in female patients with metabolic syndrome.

Material/methods: In 23 women with metabolic syndrome and 12 control normotensive women, anthropometric indices, blood pressure, and serum lipids were evaluated and an oral glucose tolerance test was performed.

Lipid-protein complexes in erythrocyte membrane in late gestosis.

Gestosis is characterized by increased rigidity of the surface and deep layers of erythrocyte membranes, impaired protein-lipid relationships, and imbalance between LPO and the antioxidant defense system. These changes determine the prognosis and complications of this condition.

[Effect of insulin on lipid peroxidation in the erythrocyte membranes of patients with insulin dependent diabetes mellitus].

The spin-probe techniques has been used to study insulin-membranes interaction in erythrocytes by insulin dependent diabetes mellitus. The lipid peroxidation has been initiated by FeSO4-ascorbate. It was found the insulin defend the lipids in control by peroxidation, but no effect in insulin dependent diabetes mellitus erythrocytes.

[Structural organization of red blood cell membranes in pregnant women with gestosis].

Activated lipid peroxidation (LPO) was found to occur with decreased antioxidative activity (AOA) in gestosis, by deteriorating the structural and functional properties of cell membranes. This enhanced the permeability of the phospholipid bilayer and altered the function of membranous proteins and the synthesis of biologically active agents, by involving the systems responsible for microcirculatory homeostasis. Enhanced membrane hydrophilicity and increased LPO and AOA are typical of the second and third trimesters of normal pregnancy.

[The structural status of red blood cell membranes in children with insulin-dependent diabetes mellitus. Examination by spin probe].

Using spin probes-stearic acid analogues, the authors investigated the microviscosity and the a/b parameter of red blood cell membranes in children with diabetes mellitus. The structural changes were correlated with altered metabolic measurements. The change in the pathway of insulin in diabetes mellitus led to the structural state of red blood cell membranes.

[ESR-spectroscopy in medical practice and biomedical research].

The authors describe the use of the ESR technique during the past 20 years. There are many examples of the application of the technique in different investigations. The authors propose the new way of training medical students to apply it.

[Mechanisms of functional disorders of the membrane receptor apparatus in pregnant women with insulin-dependent diabetes mellitus].

Studies of membrane receptor system in patients with insulin-dependent diabetes mellitus revealed that insulin resistance in pregnant patients with type I diabetes is caused by disordered cellular sensitivity to threshold physiological and submaximal insulin doses, whereas the maximal doses of the hormone normalize glucose consumption by the cells. High insulin doses intensify lipid peroxidation, normalize the status of membranous proteins, reduce the number of thiol groups, reduce AOA level in membranes, and, hence, reduce membranous capacity to bind active peroxide radicals. Structural and functional changes in red cell membranes are associated with reduced affinity of insulin receptors, reduction in the number of insulin-binding sites in membranes, this disordering intracellular effects of insulin.

[Recording of surface potential changes in erythrocyte membranes from patients with insulin-dependent diabetes mellitus using a spin probe method].

Changes in surface potential of erythrocyte membranes were studied by a positively charged analog as a spin probe. Insulin-dependent diabetes mellitus (IDDM) patients demonstrated a significant increase (by 16 +/- 2.0 mV) in negative surface potential as compared to the control.

[Structural changes in erythrocyte membranes in diabetes mellitus using spin labelled fatty acids].

Microviscosity and polarity of erythrocyte membranes of the blood of patients suffering from diabetes were studied by ESR using spin-labeled fatty acids. Structural changes were discovered 0.6-0.

[Using the spin label and probe method in medical research].

Spin probe methods applied in membrane medical research are reviewed. The results of erythrocyte membrane studies in diabetes demonstrate potentialities of the methods in medical investigations. The new data on the changes occurring in the erythrocyte membranes of patients suffering from type I diabetes are under discussion.

[The state of erythrocyte membranes in diabetes mellitus].

Study of red cell membranes in diabetics has shown that physicochemical shifts in the red cell membrane lipid bilayer, elevated lipid peroxidation, and disordered thiol compound metabolism are among the crucial aspects in the pathogenesis of diabetes mellitus. EPR spectroscopy in complex with other biochemical methods will help monitor the adequacy of therapy.

[Changes in the membrane structure of the brain microsomes in cats with electrodes implanted in the inner ear].

Using spin-labels it was shown that electrode implantation into the cats scala media resulted in structure reconstruction of microsome membranes of auditory zones in cats brain. Membrane fluidity increased but there was no change of surface potential. The changes of microviscosity were found during the first month after the implantation.

[The auditory area of the cat cerebral cortex after implantation of electrodes into the inner ear (morphologic and biophysical research)].

The article presents the findings of experimental studies of morphological and biophysical changes in the A1 hearing zone of the cerebral cortex depending on the period of the electrodes implantation in the inner ear. The studies showed that in the process of long implantation in the neurones of the hearing zone one can notice the disorders of water-electrolytic exchanges. There is a definite correlation between structural changes in microsome membranes of A1 zone and morphological data.

[Use of the spin label method for studying the structure of the brain membranes in cats with streptomycin poisoning].

The structural changes in cat brain membranes under the injections of intramuscular streptomycin which is ototoxic antibiotic have been studied. The increase of membrane microviscosity in brain areas which are the direct projection of the auditory way has been revealed using fat acidic spin probe on the basis of stearic acid. The changes in membranes of other brain areas have not been found that exhibits a specific streptomycin influence on the auditory analyzer.

[Effect of hypothyroidism on the structural and functional characteristics of the sarcoplasmic reticulum of rabbit skeletal muscles].

Structural and functional characteristics of sarcoplasmic reticulum vesicles (SRV) from skeletal muscle of normal and hypothyroid rabbits were investigated. The rate of Ca2+ absorption was decreased in hypothyroid animals and Ca2-ATPase activity in SRV of these animals was lower than that of control rabbits. The transport ratio (Ca2+/ATP) in hypothyroid rabbits was higher by 20% than in controls.

[Spin labels in the analysis of Ca-ATPase in the sarcoplasmic reticulum of rabbit skeletal muscles in hypercholesteremia].

The method of electron paramagnetic resonance with spin-labeled maleimide was used to study variation of the structure of Ca-ATPase of the sarcoplasmic reticulum (SR) in rabbit skeletal muscles under long-term hypercholesterolemia (HC). The rate of the maleimide spin label binding with Ca-ATPase of the SR was decreased in HC, which correlated with a lesser access of spin-labeled thiol groups for potassium ferricyanide and sodium ascorbate. HC led to a considerable reduction in the lability and to enhancement of hydrophobia of the spin-labeled fragment of the enzyme.

[Modification of an enzymic system for Ca2+ transport in sarcoplasmic reticulum in lipid peroxidation. Change in the molecular organization of the lipoprotein Ca-ATPase complex].

Using ESR spectroscopy of spin probes and spin labelling, the effects of lipid peroxidation (LPO) on the molecular organization of Ca-ATPase from rabbit skeletal muscle sarcoplasmic reticulum membranes were studied. Accumulation of LPO products caused an increase of the hydrophobicity and a decrease of the mobility of the Ca-ATPase polypeptide chain fragment immediately proximal to the enzyme active site. Induction of LPO in the membranes resulted in a decrease of the thermal stability of the lipoprotein Ca-ATPase complex which occurred as a biphasic process.

[Interaction of spin-labelled phosphatidyl choline with Ca-dependent ATPase from sarcoplasmic reticulum].

The interaction between 3-acyl-2-(6-doxylpalmitoyl) phosphatidyl choline used as a hydrophobic spin probe and Ca2+-dependent ATPase from sarcoplasmic reticulum membranes of rabbit and carp white skeletal muscles was studied. The spin label incorporation into ATPase preparations was performed at initial steps of ATPase isolation by incubating reticulum membranes with the spin probe in the presence of cholic acid. A comparison of the molecular mobility of the probe incorporated into ATPase preparations and into liposomes formed from ATPase phospholipids demonstrated that the presence of the protein in the membrane produces the same effect on the probe mobility as does the decrease of temperature by 10-15 degrees C.

[Interaction between free fatty acids and Ca2+-dependent ATPase from sarcoplasmic reticulum membranes].

The interaction between free fatty acids and Ca2+-dependent ATPase, an intrinsic protein of sarcoplasmic reticulum membranes, was studied with relevance to the changes in membrane permeability induced by free fatty acids. It was found that only unsaturated fatty acids increase the permeability of reticulum membranes for Ca2+, this effect being completely reversible. The increase in the membrane permeability by fatty acids is coupled to a generation of a channel for Ca2+ efflux under effect of Ca2+-dependent ATPase.