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Endothelium is an important regulator of selective permeability of the vascular wall for different molecules and cells. This review summarizes current data on endothelial barrier function. Endothelial glycocalyx structure, its function and role in the molecular transport and leukocytes migration across the endothelial barrier are discussed. The mechanisms of transcellular transport of macromolecules and cell migration through endothelial cells are reviewed. Special section of this article addresses the structure and function of tight and adherens endothelial junction, as well as their importance for the regulation of paracellular transport across the endothelial barrier. Particular attention is paid to the signaling mechanism of endothelial barrier function regulation and the factors that influence on the vascular permeability.

Chloroplast agglutination and sieve tube obliteration are related to the different plant tissues: the agglutination--to the leaf mesophyll, and the obliteration--to the axis phloem. Being equally produced by photosynthate export dynamics, both phenomena are synchronous and can be used for diagnostics of seasonal flashes and pauses of photosynthetic activity with equal success. The nature of the mobility of chloroplast and their shuttle displacements from the nuclear envelope to the cell periphery connected with export dynamics have been established. It is assumed that nuclear envelope is the base structure of the endoplasmic reticulum (ER) inside which the chloroplasts are localized. Activation of photosynthesis and sugar accumulation inside the ER induces its expansion followed by centrifugal diffusion of chloroplasts. Come back effect--ER collapse, its return to the source--can be induced by the blockade of photosynthesis. Centripetal collapse is accompanied by plastid concentration around the nuclear envelope. Displacements of ER and the chloroplasts dislocating inside it are reversible. It depends on seasonal fluctuations of photosynthesis and export intensities. Changes in the volume of sieve tubes, which are due to the same reason, are irreversible. Each seasonal wave of photosynthesis and sugar export forms new series of sieve tubes, replacing obliterated ones.

Epithelium is a key structure of tissue barriers ensuring a creation of electrochemical and osmotic gradients. There are transcellular and paracellular types of transepithelium transport of molecules and ions. Epithelial layer permeability for paracellular transport as well as restriction of lateral integrative protein diffusion in a plasma membrane is determined by apical intercellular complex including tight junctions. Integrative proteins of the claudin family are basic molecular components of tight junctions. Properties of single claudins and their complexes define the differences in a degree of epithelial permeability. The subfamily of claudins forming charge- and size-selective pores provides selective paracellular diffusion. The subfamily of claudins increasing epithelial impermeability strengthens epithelial barrier features.

Effect of hypoosmotic conditions of medium on oxygen regime of skeletal muscles of the stenohalin goby Gobius cobitus Pallas was studied under conditions of experiment. The control fish group was maintained at 12-14 %o, the experimental one - at 4.8-5.6 per thousand. Duration of the experiment - 44-45 days, water temperature - 15 +/- 1 degrees C, photoperiod - 12 day/12 night. It was established that under conditions of external hypoosmia there occurred hydration of the goby skeletal muscles and a decrease of their diffusion capability with respect to oxygen. The latter was accompanied by the tissue P(O2) decrease, which is indicated by low values of P(O2) in the venous blood outflowing from muscles. For the first 14-16 days of adaptation to the hypoosmotic medium there were restricted processes of mass transfer and oxygen utilization, which was associated with a decrease of the voluminous tissue blood flow and the blood oxygen concentration. These changes occurred on the background of the blood plasma hydration and a decrease of the number of circulated erythrocytes, and then they were completely compensated.

This review will focus on the systematization of knowledge about structure of macroglobulin signaling system, which includes macroglobulin family proteins (alpha-2-macroglobulin, alpha-2-glycoprotein, pregnancy associated plasma protein A), their receptors (LRP, grp78), ligands (proteinases, cytokines, hormones, lipids, et al.) transforming and transcriptional factors for regulation of macroglobulins synthesis. After reviewing the functions of macroglobulin signaling system, and mechanisms of their realization, we discuss the complex and significant role of this system in different physiological and pathological processes.

The mechanisms of participation of multidrug-resistance proteins (MRPs) in sex difference pattern of drug efficiency and side effects have been analyzed. MRPs structure, their tissue and cellular localization, substrate specificity, and functions have been considered. Regulation of expression and activity of MRPs by endogenous metabolites, signal compounds, including sex hormones, as well as by drug agents have been represented. The role of nuclear receptors in the regulation of MRPs expression has been demonstrated. The data on sex differences in hepatic and renal MRPs expression and expression of nuclear receptors, participating in their induction, have been shown. The participation of MRPs in the formation of sex differences of drug pharmacokinetics has been discussed. Sex differences in representation and functional activity of MRPs in such excretory organs as liver and kidney was concluded would play the essential role in sex dependence of pharmacokinetics and efficiency of drug action.

It was shown recently, that high affinity Cu(I) importer eukaryotic protein CTR1 can also transport in vitro abiogenic Ag(I) ions and anticancer drug cisplatin. At present there is no rational explanation how CTR1 can transfer platinum group, which is different by coordination properties from highly similar Cu(I) and Ag(I). To understand this phenomenon we analyzed 25 sequences of chordate CTR1 proteins, and found out conserved patterns of organization of N-terminal extracellular part of CTR1 which correspond to initial metal binding. Extracellular copper-binding motifs were qualified by their coordination properties. It was shown that relative position of Met- and His-rich copper-binding motifs in CTR1 predisposes the extracellular CTR1 part to binding of copper, silver and cisplatin. Relation between tissue-specific expression of CTR1 gene, steady-state copper concentration, and silver and platinum accumulation in organs of mice in vivo was analyzed. Significant positive but incomplete correlation exists between these variables. Basing on structural and functional peculiarities of N-terminal part of CTR1 a hypothesis of coupled transport of copper and cisplatin has been suggested, which avoids the disagreement between CTR1-mediated cisplatin transport in vitro, and irreversible binding of platinum to Met-rich peptides.

Aim: Study of extracellular membrane nanovesicles production by Aeromonas hydrophila and Aeromonas salmonicida bacteria on a subcellular level., Materials and Methods: 4 strains of A. hydrophila: 342-1, E 8-8, H 336 and H 1-6-05 and 1 strain of A. salmonicida A-450 as well as intact Wistar line rats were used. Methods of transmission electron microscopy: ultrathin sectioning and negative contrasting were used. RESULTS. A. hydrophila and A. salmonicida bacteria produced in pure cultures excrete into the environment extracellular membrane nanovesicles. The size of these vesicles varies from 20 to 200 nm in diameter. The process of gemmation from bacterial cell and possibility of obtaining isolated membrane nanovesicles preparations is shown. These vesicles are detected in ultrathin sections of apical surface of intact rat intestine among accumulations ofparietal microorganisms that colonize mucous membrane. Extracellular membrane nanovesicles excreted by aeromonas are analogous by size and ultrastructure to vesicles of other species of gram-negative bacteria described in the literature., Conclusion: During production of A. hydrophila and A. salmonicida bacteria in vitro nanovesicles are formed from the outer membranes of the cells and excreted into the environment, the nanovesicles are similar to those detected in ultrathin sections of the surface of intestine of rats among accumulations of parietal microorganisms and in glycocalix between epitheliocyte microvilli.

The regulatory decrease in the volume of principal cells of collecting ducts to hypoosmotic shock has been investigated experimentally and using the mathematical modeling. A mathematical model of the response of collecting duct principal cells to hypotonic shock has been constructed on the basis of the experimental time course of changes in cell volume measured by the fluorescent dye Calcein. It was shown that the regulatory decrease in volume under hypotonic conditions occurs via a marked release of osmolytes and is accompanied by a decrease in water permeability of the cell membrane. The mathematical modeling of transmembrane transport processes allowed us to quantitatively estimate the changes in membrane water permeability, which decreased tenfold, from 2 x 10(-1) cm/s to 2 x 10(-2) cm/s. It was also shown that the effective regulatory decrease in the volume of collecting duct principal cells in hypotonic medium results from a significant increase in membrane permeability for K+, Cl-, and organic anions.

Here we have shown that 24 hours after addition of zeatin to the nutrient solution the cytokinin content in xylem sap of wheat plants appears to be about 10 times lower that in the nutrient solution. Cytokinins accumulated mostly in roots and not in shoots of treated plants. These data demonstrate the existence of some barrier on cytokinin pathway from the nutrient solution to the plant shoot. With the help of Sudan III an increase in lignin and suberin deposition in the endodermis could be detected, being stronger with the increase in the distance from the root tip. The increase in deposition of suberin and lignin coincided with the decrease in cytokinin immunolabeling in root cells revealed with the help of monoclonal cytokinin antibodies and the second gold-labelled antibodies. Simultaneously exogenous cytokinins accumulated in root stele cells showing that the Casparian band was not only barrier on cytokinin pathway to plant shoot. It is concluded that high cytokinin immunolabe ling in the stele parenchyma cells around the stele vessels demonstrated accumulation of cytokinins by these cells, which could be important in regulation of cytokinin loading to the xylem vessels during there transport to the shoot. The role of cytokinin transporters is discussed.

Biochemical investigations of red blood and oxygen transportation by erythrocyte hemoglobin were performed in volunteered for chamber experiments (0.14 MPa) with normal and hypoxic oxyargon medium (O2-Ar). Erythrocyte metabolism, lipid and phospholipids spectra, and effectiveness of oxygen release and retention by hemoglobin were studied in the baseline data collection period, on day 6 in hyperbaric and normoxic O2-Ar medium (13.7% O2), on day 3 in hyperbaric and hypoxic O2-Ar (9.9% O2) and on day 1 and 10 during the post-experiment rehab. Elevated pressure, hypoxia and ensuing decompression revealed an ATP reduction that could be a result of shifts on the membrane level and increased G6PD activity associated with cell reparation processes. Changes in membrane lipid and phospholipids composition point to an altered phase state of plasmatic membrane, i.e., increased viscosity which is indicative of possible impairment of membrane permeability As a rule, hyperbaria impacted oxygen transportation in blood of the subjects; effect of hypoxia combined with hyperbaria was not uniform ranging from none to decreasing or increasing oxygen transportation that can be extenuated by selectivity and individual sensitivity to the factors in the experiment Loss of O2 transportation efficiency by hemoglobin is most likely connected with the increase of plasmatic membrane viscosity that could affect hemoporphyrin conformation of membrane-bound hemoglobin and obstruct oxygen transport though membrane.

This review briefs the modem concepts of the diversity of hemoglobin functions. The hemoglobins discovered in the representatives of all kingdoms of living nature are described. Specific structural features of various groups of these proteins, including flavohemoglobins and truncated hemoglobins, are discussed. The transport, catalytic, and sensory functions of these proteins are described as well as their roles in oxidative, nitrosative, and carbonyl stresses and the changes in their functions caused by modifications of the molecule. The issues of hemoglobin origin and evolution are discussed.

The SGA/TFTC complex plays an important role in the regulation of transcription. We have examined the significance of the gene positioning in the nucleus for its transcription and subsequent export of nascent mRNA. It was demonstrated that E(y)2 protein was a subunit of the SAGA/TFTC histone acetyl transferase complex in Drosophila and that E(y)2 concentrated at the nuclear periphery. An interaction between E(y)2 and the nuclear pore complex (NPC) was demonstrated, as well as that SAGA/TFTC also contacted the NPC at nuclear periphery. In addition, it was shown that E(y)2 formed complex with the Xmas-2 protein (X-linked male sterile 2) both in normal conditions and after heat shock. Importantly, the E(y)2 and Xmas-2 knockdown decreased the contact between the heat-shock protein 70 (hsp70) gene loci and the nuclear envelope before and after activation, and interfered with the transcription. Thus, E(y)2 and Xmas-2 together with SAGA/TFTC functioned in the anchoring of a subset of transcription sites to the NPCs to achieve efficient transcription and mRNA export.

A nonconventional approach to the measurement of succinate transport through plasmalemma is proposed. It is based on the conditions in which the succinate oxidation rate is limited by transport through plasmalemma. Impermeable specific inhibitor of plasmalemma dicarboxylate transporter was employed as a tool to optimize conditions for the transport activity assay. For this purpose yeast culture was grown in synthetic medium under selected conditions. After aerobic preincubation of S. cerevisiae cells at 0 degree C (instead of incubation at 15 degrees C), the rate of endogenous respiration decreased substantially and was stabilized during measurements at a level that was five times lower than oxidation rates in the presence of exogenous substrate. This approach allowed for the reproducible determination of K(M) for the dicarboxylate transporter (7.3 +/- 2.1 mM) within a half-hour period. The advantages and drawbacks of this fast, but indirect, assay of slow substrates transport into the cell are compared with conventional methods.

We have studied the morphology and vein branching of rosette leaves in Arabidopsis thaliana mutants as and sa, which proved to be alleles of the A. thaliana AS1 and AS2 genes, respectively. We have also analyzed the localization of bioactive auxin, as measured by the expression of the DR5::GUS transgene, as well as the expression patterns of BP, as measured by the expression of the BP::GUS transgene in leaves of the mutants. In mature leaves of the mutants, BP was expressed ectopically. Furthermore, the mutants showed some defects in the localization and concentration of free auxin compared to the wild type. Our results of studying new alleles of AS1 and AS2 support their role in control of class I KNOX genes and auxin transport.

Plasma membrane Ca2+-ATPase is the calcium pump that extrudes calcium ions from cells using ATP hydrolisis for the maintenance of low Ca2+ concentrations in the cell. Calmodulin stimulates Ca2+-ATPase by binding to the autoinhibitory enzyme domain, which allows the access of cytoplasmic ATP and Ca2+ to the active and transport cites. Our kinetic model predicts damped oscillations in the enzyme activity and interprets the known nonmonotonous kinetic behavior of the enzyme in the presence of calmodulin. For the parameters close to the experimental ones, the kinetic model explains the changes in frequency and damping factor of the oscillatory enzyme activity, as dependent on calmodulin concentration. The calculated pre-steady-state curves fit well the known experimental data. The kinetic analysis allows us to assign Ca2+-ATPase to the hysteretic enzymes exhibiting activity oscillations in open systems.

The effects of malate, succinate, and glutamate on the kinetics of changes in the pH gradient (delta pH) and membrane potential (delta psi) on the peribacteroid membrane (PBM) of the symbiosomes of bean root nodules varying in age were recorded spectrophotometrically. Addition of all the tested metabolites to potassium-free incubation medium stimulated a passive acidification of the peribacteroid space (PBS) and dissipation of delta psi in PBM of young developing nodules in the presence of the K+/H+ antiporter nigericin in the medium. However, in mature nodules with a high nitrogen-fixing activity, only malate and succinate (but not glutamate) increased delta pH during both passive and ATP-dependent PBS acidification. Dicarboxylates also caused dissipation of both delta pH in the presence of nigericin in the medium and delta psi generated on PBM by H+-ATPase. A decrease in the effects of metabolites on delta pH and the absent activity of the PBM H+ pump were observed in the aging nodules. The obtained data on the changes in deltapH and dlta psi caused by the metabolites in question suggest that PBM is permeable for all these metabolites only in young nodules. Only malate and succinate (but not glutamate) are transported through PBM in mature nodules; and the rate of metabolite translocation through PBM in aging nodules is decreased.

The spontaneous contractile activity of isolated lymph nodes and the lymph flow from intestine lymphatic vessel in antiorthostatic posture of rats with an inclination angle of 30 degrees during 7-14 days, was decreased. Contractions of the rat lymph nodes in response to actions of adrenaline, acetylcholine and histamine were diminished. There are changes of biochemical components of lymph and blood plasma with simultaneous decrease of the blood plasma volume. It is concluded that the lymphatic system on antiorthostatic posture plays the compensatory role with the purpose of stabilization of homeostasis in the brain.

Antinociceptive activity of dalargin (7.5 mg/kg) adsorbed on poly(butyl)cyanoacrylate nanoparticles with different coating was studied on outbred albino mice by the tail-flick test. poly(butyl)cyanoacrylate nanoparticles without coating did not increase the antinociceptive activity of dalargin and hence, did not increase its transport across the blood-brain barrier. poly(butyl)cyanoacrylate nanoparticles coated with apolipoprotein B, apolipoprotein E, and polysorbate 80 increased the transport of dalargin across the blood-brain barrier. Delivery of dalargin to the brain was most effective in case of using poly(butyl)cyanoacrylate nanoparticles with polysorbate 80 coating and subsequent supercoating with apolipoprotein E.

In the experiments with seeds of Ericaceae, gemmuls of Spongia, statoblasts of Bryozoa, resting eggs and ephippia of Crustacea the hypothesis on selective permeability of propagule shells was tested. It was shown that the propagules are activated and develop until the moment of destruction of shell in the solutions of phenols, formaldehyde, CuSO4, K2Cr2O7, HgCl2, Ag2SO4, AgNO3, CoCl2 and NiSO4. It means that propagule shell is impermeable for these poisons but permeable for water and oxygen. The effectiveness of barrier can be various in different species but in some cases it is very high. The development of resistance to poisons of anthropogenic origin that were not familiar to organism earlier can be considered as an example of the rule (Rasnitzyn, 1971) according which relation between environmental variability and power of regulator is shifted to the priority of regulator. Selectively permeable shell for many organisms is a common adaptation that allows colonization of land and continental waters.

The authors of the review discuss the present-day state of and promising approaches to directed delivery of biological agents into the brain. Special attention is drawn to micellar and liposomal transport through the blood-brain barrier (BBB) targeted by immunochemical vectors, such as native or hydrophobized antibodies to specific antigens located at the BBB or in the brain parenchyma.

The appearance of this review concerning the nitric oxide transport in a blood vessel wall is connected with the authors' interest in vessel tone regulation. The introductory part contains basic equations for resistive vessels, an outline of processes occurring in smooth muscle and endothelial cells, and the simulation of these processes. As a rule, the description of nitric oxide diffusion and reactions in blood vessels is given in the order of increasing complication of the models. Primary attention is given to the consideration of systems with endothelial production of nitric oxide, but articles considering other sources of nitric oxide are also reviewed. The theoretical methods of evaluating the parameters that are important for modeling but hardly measurable are described.

Phylogenetic and ontogenetic relationships between the plastids, cell endoplasmic reticulum, and plant transport communication have been reviewed. The initiating role of plastids (endosymbionts) in the origin of endoplasmic reticulum (buffer zone of endosymbiogenesis) has been shown, as well as a similar role of endoplasmic reticulum in the development of transport communication of xylem and phloem. Plastids, sugars and transport system for their distribution can be interpreted as leading sections in the mechanism of developmental control: gene expression of nuclear genome and genome of organelles, cell and tissue differentiation, and plant morphogenesis. The conflict between the bulk of plant genome and low percentage of its realization is explained as a result of limitation of the nuclear genome realization by plastid genome. The concept of development as applied to plant ontogenesis has been critically analyzed. The possibilities of the concept correction by with the help of symbiogenetic hypothesis are discussed.

Simple methods for the registration of translational diffusion of water in apoplast and vacuolar and cytoplasmic symplasts were developed. The methods are based on spin-echo NMR with a pulsed magnetic field gradient and are realized by preliminary inversion of magnetization and the use of paramagnetic doping. It was shown that the diffusion of a part of root water in segments of mais roots is more enhanced than that for the bulk water. The results are explained by the appearance of the rotational movement of the protoplasm and in terms of the hypothesis of water transfer along the apoplast, which balances the cytoplasmic symplast.

Water permeability of the basolateral membrane was estimated in isolated fragments of OMCD or IMCD in the Wistar rats. Apical surface of the fragments was blocked with oil injected into the lumen. Apparent water permeability coefficient (Pf) was measured by the rate of epithelium swelling following transition from hypertonic to isotonic medium (600 mOsm to 300 mOsm). Water deprivation caused significant increase in the Pf value in OMCD and IMCD fragments. Desmopressin (10(-8) M) increased water permeability in hydrated rats both in OMCD and IMCD. Mercury chloride decreased the Pf and abolished the effect of desmopressin in reversible manner. Estimation of aquaporins 2, 3, 4 mRNA content in the renal medulla was performed by semi-quantitative RT-PCR. Content of AQP4 and AQP2 mRNA in dehydrated animals was significantly higher than in hydrated ones both in outer medulla and inner medulla. Expression of AQP3 increased during dehydration only in the inner medulla. The findings reveal that water permeability of OMCD and IMCD can be increased by physiological stimuli, e.g. water deprivation. The activation of gene expression of the key elements of vasopressin signal system seems to contribute to this reaction.

By means of in vivo microdialysis combined with HPLC analysis, we have shown that glutamate extracellular level in the rat n. accumbens increases during a forced switch in behavioral strategy. When infused in the n. accumbens, a Na+ channel blocker tetrodotoxin (TTX, 1 microM) completely prevents this increase whereas a potent cystine/glutamate exchanger blocker (S)-4-carboxyphenylglycine ((S)-4-CPG, 5 microM) has no effect. In contrast, TT (1 microM), infused in the n. accumbens, fails to significantly alter basal level of extracellular glutamate in this region whereas (S)-4-CPG (5 microM) produced a significant decrease. Our data suggest that basal and factional glutamate releases in the n. accumbens are differently regulated. The source of basal glutamate release is a non-vesicular release via cystine/glutamate exchanger. Functional glutamate release observed during a forced switch in behavioral strategy derives from vesicular synaptic pool.

The effect of a direct electric current on electrolyte transport through plant tissues was studied by applying it to 10-mm fragments of the mesocotyls of etiolated maize seedlings, similar fragments of one-year linden shoots with the normal conducting system and without vascular bundles, and isolated elements of the xylem and cell wall segments. At the current density and voltage of 9-38 microA/mm2 and 10-20 V, electrolyte solutions in plant tissues always moved toward the cathode. The results suggest that electroosmosis is one of the factors responsible for changes in solution transport through the conducting plant tissues that occur under the effect of electric current.

Dendritic cells play a key role in initiation and regulation of adaptive immunity against pathogens and tumors, as well as in autoimmune disease. In this article we review recent data regarding distribution of dendritic cells in the central nervous system, their role in responses and possible role in pathogenesis of multiple sclerosis. We also consider possibilities to use dendritic cells as immunotherapeutic targets in multiple sclerosis.

Using the voltage-clamp technique, a possible role of protein kinase C in regulation of Na+ transport in the skin of the frog Rana temporaria was investigated. It was shown that protein kinase C activator phorbol ester 12-myristate 13-acetate (PMA), applied to the apical surface of the skin, stimulated transepithelial Na+ transport, measured as amiloride-sensitive short-circuit current, and also increased such electrical characteristics of frog skin as the open-circuit potential and transepithelial conductance. PMA exerts a similar stimulation effect on Na+ transport across the tadpole skin. Specific inhibitors of protein kinase C, chelerythryne or H-7, almost fully prevented the PMA-induced stimulation of Na+ transport. These data support a concept that the response to PMA was indeed mediated by PKC activation. The results are compatible with the important role played by protein kinase C in regulation of transepithelial Na+ transport in the skin of R. temporaria.

In 88 patients with rheumatoid arthritis lipid-protein spectrum of the blood serum were determined biochemically and by means of nefelometric technique, C-reactive protein (CRP) was measured with enzyme immunoassay. An increase in CRP concentration was associated with lowering of apoA1 and HDL FL, triglycerides. Thus, elevation of CRP in RA reflects not only activity of inflammation but also defects in serum lipid-transport system by the atherogenic type.

VNTR-polymorphism of the gene of dopamine transporter (DAT) in men of the Russian and Tatar nationalities with acute alcoholic psychoses was analyzed by method of the polymerase chain reaction. There were no differences in the distribution of frequencies of genotypes and alleles of DAT gene between the populations examined. There was association between an allele variant with 9 units of DAT gene repetition (in homozygous state first of all), and early development of alcoholic dependence and acute alcoholic psychosis.

The review is mainly devoted to the development of ideas about absorption, or transport, of basic nutrients in the small intestine in humans and higher animal. The absorption processes have been characterized on the example of such substances, vital for organism, as carbohydrates and proteins. The review considers a molecular structure of transporters--protein molecules, which take part in a transfer of the products of lumenal and membrane digestion of carbohydrates (glucose, galactose, fructose) and proteins (amino acids, oligopeptides) across the enterocyte membranes. An information is presented about genetic disturbances of transport of certain amino acids during such diseases as Hartnup disease, cystinuria, and iminoglycineuria.

The role of transport activity of Acholeplasma laidlawii plasmatic membrane in the development of resistance to ciprofloxacin was investigated. It was shown that ethidium bromide used as fluoroquinolone analogue in plasmatic membrane efflux pump was accumulated in ciprofloxacin-resistant cells in much less amount. It was estimated that ethidium bromide efflux depended on temperature, glucose and transmembrane electro-chemical proton potential. Inhibitors of efflux systems--reserpine and verapamil enhanced the ethidium bromide accumulation much more intensively in ciprofloxacin resistant cells. The results of investigation allowed to consider the existence of active efflux system for toxic agents in acholeplasma; in the case of ciprofloxacin-resistant strain these systems are inducible.

There have been presented the results of studying the reactivity of leucocytes with respect to tuberculin and monspecific migration activity of leukocytes in the cosmonatus pre flight and after completion of orbital expeditions of various duration are presented. In some cosmonauts tuberculin rearranged migration of leukocytes. This may bear witness to activisation of the immunity system in response to the antigens which had been already familiar to test-subjects. Experimental data pointed to significant changes in leukocyte mobility in 12 out of 28 cosmonauts examined on days 1 and 7-14 of recovery after the first or repeated long-duration space missions indicating some functional disorders in the phagocytic link which may lead to a typical decline in human resistance to infections.

The main pathways of regulation of cytoplasm Ca2+ level with hormones and growth factors, as well as mechanisms of regulation of G-proteins, phospholipase C, Ca-channels, adenylate cyclase, guanylate cyclase, and protein kinase C, are discussed. Regulation of cytoplasm Ca2+ in vascular and blood cells with inositol phosphates, cAMP and cGMP, is stressed. The review summarises data on membrane receptors, G-proteins, protein kinases and their targets involved in regulation of Ca2+ turnover in platelets, endothelial and smooth muscle cells.

A microfiltration method was used to study the mechanism of pantothenic acid transport in the membrane vesicles of the rat small intestine brush margin. The vitamin uptake proceeded to inner space of the vesicles and was enhanced in presence of sodium ions. The findings suggest that the vitamin transport across the membrane of the small intestine brush margin is mediated by a carrier and proceeds via a Na(+)-co-transport mechanism.

Interrelations among changes in 11-oxycorticosteroids (11-OSC) in blood plasma, catecholamines (CA), and acetylcholinesterase (AChE) activity in nerve fibres of the thymus, as well as qualitative content and proliferative capacity of thymic and blood cells under the effect of the rat recombinant interleukin-1 beta (IL-1 beta) normally and under conditions of hypothalamic-pituitary-adrenocortical depression, were studied. The changes were the most obvious within 15 and 120 min following the IL-1 beta administration: elevation of the 11-OSC, increase in the CA content, and decrease in the AChE activity in thymic nerve fibres. Preliminary administration of dexamethasone prevented the effects.

Our previous communication No. 1 presents a mathematical definition of dynamic hematocrit and rate of erythrocyte movement, based on microvessel hemodynamics model. Now we offer a mathematical model of convective diffusion oxygen transfer in the erythrocytic cylinder-plasma system. Another definition of erythrocyte movement rate is offered and a solution of two equations which permitted its definition by measured parameters. A series of practical formulae for estimating microhemodynamics is derived, which can be used in clinical practice. The proposed model has been used in cardiosurgery department of Research Center of Surgery.

Mesenteries, cornea, lens and costal cartilages, nourished, as it is commonly believed, diffusely, were investigated by dye injection into vascular bed, and using luminescent and electron microscopy. The presence of regular nonvascular microcirculation pathways (interstitial canals) providing fluid passage from blood vessels into interstitium and consequently through the opened interendothelial contacts in the lymph capillaries into the lymphatic vessels was found when examining jejunal mesentery. Findings on the existence of extravasal paths of mobile tissue fluid were obtained after examination of avascular tissue of cartilage, cornea and lens as well. Their presence adds to reported data on lymph formation and allows to reconsider such unclear items as nonvascular organ nutrition, deficiency of primary lymph in prenodular lymph vessels and experimental remodelling of elephantiasis.

A prolonged cold adaptation decreased the lipid content and increased free fatty acids in homogenate of skeletal muscles. It also seems to decrease the efficiency of the calcium-ATPase resulting from non-saturate fatty acids effect upon sarcoplasmic reticulum membranes.