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Two recombinant proteins with three copies of the ectodomain of the conserved influenza protein M2 (M2e) of influenza viruses were developed: A (H1N1)pdm09, A/Kurgan/05/05 (H5N1), and M2e consensus sequence of the human influenza A virus (H1N1, H2N2, H3N2) based on flagellin and core antigen of hepatitis B (HBc). The first recombinant protein comprised flagellin fused to three tandem copies of M2e, the second preparation was based on non-covalent interaction between M2e peptides and HBc. The immunogenicity of two preparations was comparatively tested. A covalent linkage of flagellin with M2e significant increased the immunogenicity of the target antigen compared with non-covalent interaction M2e and HBc. Flagellin as a protein carrier of M2e induced mainly IgG1 subclass, whereas HBc stimulated more balanced Th1/Th2 response. Our study showed a decrease in the viral titers in lung tissues of immunized mice after lethal challenge of A/PR/8/34 (H1N1). The study revealed a possibility to obtain a vaccine preparation with equal immunogenicity both against human influenza viruses and highly pathogenic avian influenza viruses.

The cytolytic form of hepatitis E virus reproduction in FRhk-4 cells is described. The cytopathic effect was observed by days 6-7 of the 25th passage in this cell culture. Reverse transcription with polymerase chain reaction were used to study virus reproduction daily for 10 days postinfection. The virus replication starts on day 4 after inoculation. The development of the cytopathic effect depended on the serum concentration in culture medium, whereas the virus replication did not depend on this factor. The replicative form (-RNA) of viral RNA appeared on day 4 postinoculation, as did the new genomic one (+RNA).

Different types of interneurons producing nitric oxide in human brain motor cortex were studied by means of histochemical reaction to NADPH diaphorase--the marker of nitric oxide synthase. Non-synaptic dendrito-, axo- and somatovasal contacts between typical smooth and spinous checking interneurons were shown. A hypothetic scheme of local blood circulation control is represented, after which these cells, exerting inhibitory synaptic action on pyramidal neuron at the same time cause vasodilatation by secreting nitric oxide near to the capillary. Scientific Research laboratory of Biological Mechanisms of Structural Maintenance of Homeostasis, Russian Medical University, Moscow.

To study the relative roles of creatine kinase (CK) and adenylate systems in cardiac energy turnover, the effect of CK inhibitor, iodoacetamide- (IAA, 0.5 mM), and 2-deoxyglucose-(DOG, 2 mM) induced) 65% depletion of adenine nucleotides at slightly decreased CK flux was determined in isolated rat heart. Both substances did not substantially affect contractile parameters of the isovolumic heart. However, an augmentation of cardiac work induced by isoproterenol addition was feeble and transient in IAA-treated hearts while the response of DOG-treated hearts was well preserved. The cardiac failure after IAA treatment was associated with irreversible fall in myocardial ATP content as evidenced by 31P-NMR technique. Furthermore, these hearts were unable to perform cardiac pump function due to insufficient cardiac filling and distensibility. The DOG-treated hearts exhibited 50% reduction in the pump function and were able to increase their work in elevated resistance. The results suggest that CK pathway is extremely important for both full cardiac relaxation and maximal contractile function.

Treatment of perfused rat hearts with 0.5 mM iodoacetamide (IAAm) for 15 min at different workloads resulting in a nearly complete inhibition of creatine kinase (CK, 99%) was followed by a rapid decline of the phosphocreatine (PCr) level (30%) and a 2-fold increase of the P(i) level which then stabilized. Conversely, the ATP content started to drop monotonously at the beginning of the IAAm washout and reached 30% 90 min after the IAAm removal under medium load. Under low workload the ATP decay occurred at later periods. Neither the ADP-stimulated mitochondrial respiration in skinned fibers, nor the Ca(2+)-stimulated ATPase activity of myofibrils was affected by IAAm treatment. The sensitivity of the resting tension of skinned fibers to Ca2+ tended to a slight increase. The cardiac work index (PRP-pressure-rate product) decreased by 25%, while the end diastolic pressure (EDP) rose by 15 mm Hg when IAAm acted under medium load. In contrast, under low work these parameters were practically stable. The hearts poisoned with IAAm performed a two times lower maximal work and had reduced (by 35%) oxygen consumption rates. The efficiency of energy utilization for mechanical work decreased by 40%. The changes in PRP and EDP correlated with the cytosolic [ATP]/[ADP] ratio in such a way that the decrease in the latter was associated with a decrease in PRP and the elevation of EDP. These data suggest that the creatine kinase system is necessary for the effective translation of a high [ATP]/[ADP] ratio from the intermembrane space of mitochondria to the cytoplasm, myofibrils and ionic pumps. This provides a high level of mechanical work and good relaxation of the left ventricle and protects cytosolic adenine nucleotides from the breakdown.

The cardiac output of isolated working rat heart and left ventricular pressure were estimated in either almost complete inhibition of creatine kinase by iodoacetamide or predominant fall in adenine nucleotides (AdN) content induced by 2-deoxyglucose treatment. In the former case, a profound cardiac pump failure was observed despite almost normal levels of myocardial AdN and phosphocreatine. Those hearts could not maintain the aortic output at standard load due to lower LV systolic pressure, that was accompanied by increased minimal and maximal diastolic pressures by 5-7 mm Hg as well as by LV diastolic stiffness. As LV systolic pressure in those hearts was unchanged in retrogradely perfused and unloaded hearts it might be suggested that the cardiac pump failure was caused by the decreased LV distensibility. On the contrary, deoxyglucose treatment that resulted in 70% fall in the AdN content was accompanied by only moderate reduction of the cardiac output and insignificant changes in LV diastolic pressure and stiffness. The results suggested that creatine kinase plays a crucial role in the maintenance of normal myofibrillar compliance, which is necessary for cardiac filling and pump function.

Functional and metabolic response of an isovolumically perfused heart of a rat to isoproterenol (0.1 microM) has been studied. A heart with the normal content of adenine nucleotides (AN) and phosphocreatine (PCr) as well as that with the 5-fold reduced AN content (with 2-deoxyglucose treatment) significantly increased cardiac work index (PRP), maximal contraction rate (MCR) and maximal relaxation rate (MRR) (by 50, 30-40 and 100-150%, respectively). The effect was preserved for all the period of the hormone action (30 min) and was followed by a temporary decrease in the PCr content. The heart with an inhibited unidirectional flux of metabolites through creative kinase (CK) and normal level of AN responded to the hormone by the slower and decelerated growth of the function and in the heart with almost completely iodoacetamide (IAAm)-blocked CK the functional response was minimal and transient. In the latter a significant and irreversible decline in PCr and ATP content and a concomitant rise of inorganic phosphate took place. Both basal and isoproterenol-stimulated adenylate cyclase activity remained unchanged after IAAm treatment. An increase in PRP correlated with the elevation of the cytosolic ADP concentration, however, correlation was not uniform for different experimental groups. These data show significance of the creatine kinase system not only for maintenance of maximal work but also for a rapid functional response to the catecholamine stimulation.

Effect of some preparatory methods to make ready earthworm tissues for electron microscopical investigation has been studied in order to reveal structural components of the vascular wall. The method for an immediate fixation of the earthworm tissues in liquid nitrogen with a subsequent additional fixation in cooled 2.5% glutar aldehyde, applied in combination with OsO4-thiocarbohydroside-OsO4 method is optimal. This method of samples preparation gives a reliable information concerning existence of an internal--endothelial--lining in the earthworm vessels. A conclusion is made on a qualitatively new level of cell differentiation of the internal vascular lining in the earthworm, which is called phase of blast transformation of endotheliocytes.

The effect of NADH, succinate and ATP on the sensitivity of a number of energy-dependent functions of submitochondrial particles ot phospholipases A, C and D has been studied. It has been shown that in the conditions of oxidation of NADH and succinate by oxygen and also of ATP hydrolysis, the decrease in the phosphorylating activity of the particles under the action of phospholipases C and D accelerates. No such acceleration has been observed with phospholipase A. For other two functions, i. e. reverse electron transfer (ATP-dependent NAD+ reduction by succinate) and ATP-dependent transhydrogenase reaction the results proved to be different. Oxidizable substrates and ATP promoted the maintenance of these functions in the presence of phospholipase A, but did not retard their suppression by phospholipases C and D. The effects of NADH, succinate and ATP on the sensitivity of different energy-dependent functions of submitochondrial particles to phospholipases A, C and D could be removed by the uncoupling agent carbonyl cyanide-m-chlorophenyl hydrazone. The conclusion is made that the effects revealed are associated with an increase in the sensitivity of coupling sites II PAND/OR III to phospholipases C and D and with a decrease in the sensitivity of sites I and IV to phospholipase A on energization of submitochondrial particles.

The kinetic parameters of the submitochondrial particles cytochrome chain obtained from steady-state kinetics were studied for pH dependence. The life-times of the activated states (tau) for cytochrome pairs b leads to c1 and a leads to a3 are shown to bear dissimilar dependence on pH of the medium, while for cytochrome pairs c1 leads to c and c leads to a they display practically no pH dependence at all. The rate constants of the non-activated state (alphai-kiCo) decreased for the pair b leads to c1 and increased for a leads to a3 with the increase of pH from 6.5 to 8.5. The apparent pK values obtained therefrom were 7.2 and 8.9, respectively. A kinetic model is proposed suggesting that local pH in the mitochondrial membrane, dependent on the rate of electron transfer, may be a controlling factor for the ratio of activated and non-activated carrier states. The model is in good consistence with the experimental dependences of k'i on V and the pH dependences of alpha2 for b leads to c1 and a leads to a3. It also gives a qualitative prediction for the pH dependences of the ordinate intercepts of the straight lines in l/(k'i--alphai) vs. l/V plots. The rate constants for the diffusion of hydrogen and hydroxyl ions in the membrane are estimated on the basis of our kinetic data to be 10(4)--10(5) s-1 and 10(2)--10(3) s-i, respectively.

3-Phosphono-2-imino-1-methyl-4-oxoimidazolidine (PIMOI), AMP and p-nitrophenyl phosphate (pNPP) were dephosphorylated in the presence of rat heart cytosol at 37 degrees C pH 6.3 at the rates of 0.71, 0.45 and 1.07 mumol/mg X h, respectively. When mixed together, these compounds inhibited the hydrolysis of each other, which points to the participation of common enzyme(s) in this process. The inhibitor of 5'-nucleotidase (alpha,beta-methylene)-ADP, did not affect PIMOI cleavage and moderately inhibited AMP hydrolysis (by ADP, did not affect PIMOI cleavage and moderately inhibited AMP hydrolysis (by 30-50%), thus suggesting that acidic phosphatases are responsible for PIMOI and AMP hydrolysis under these conditions (pH 6.3). Phosphocreatine (PCr) and phosphocyclocreatine (PcCr) were stable to hydrolysis by the cytosolic fraction. However, addition of AMP to the medium containing PCr or PcCr resulted in AMP phosphorylation down to ATP due to the effects of these phosphagens and, probably, of microcontaminations of ATP. This was followed by gradual disappearance of PCr or PcCr and by accumulation of Pi as a result of the "ATPase" activity in the cytosol. The hydrolysis of AMP, PIMOI and p-NPP was sensitive to sulfhydryl reagents [5,5'-dithio-bis-(2-nitrobenzoate) and, in part, 2,4-dinitro-fluorobenzene] and fluoride ion. Thus, PIMOI is a competitive substrate of acidic phosphatases in heart cytosol with respect to AMP and p-NPP. This may partly explain the protective effect of PIMOI on ischemic myocardium.

The dependence of the forward pyruvate kinase reaction on the concentrations of ADP and Mg2+ was studied. It was shown that high total ADP concentrations (2-15 mM) exceeding total Mg2+ concentration in the medium lead to the inhibition of the pyruvate kinase reaction, whereas relatively high Mg2+ concentrations (up to 15 mM) do not cause any inhibition. The kinetics of the reaction can be described in the best way by a scheme incorporating the active PEP . E . Mg2+ . Mg . ADP complex and dead-end complexes containing free ADP. An analysis of the experimental data allows to determine all coefficients of the rate equation and to calculate the values of all kinetic parameters. The values of the constants obtained were used for mathematical simulation of the reaction on the basis of the kinetic scheme given. The mathematical model obtained describes satisfactorily the experimentally determined dependences, which is indicative of the correctness of the model.

Steady-state kinetics of electron transfer through the cytochrome chain of uncoupled ultrasonic submitochondrial particles at different pH values were studied. The rate constants calculated according to Pring's equation (k1=V/Prpoxt i+1) were found to increase linearly with the increase in the rate of electron transfer. Linearity was observed, however, only at relatively low rates of electron transfer. Several kinetic models were developed and analysed to fit the experimental data on the basis of the suggested activation of respiratory chains induced by their functioning. The best agreement with the experimental data was obtained with the model implying that the rate of activation of the electron carriers is directly proportional to the overall rate of electron transfer and the portion of non-activated respiratory chains in the system. It followed therefrom that electron transfer through already activated chains induced activation of adjacent non-activated chains. This model made it possiple to determine the rate constants for non-activated (ki) and activated (k) carrier states and the life-times of activated carriers (tau).

Sarcolemmal preparations isolated from rat and guinea pig hearts mostly consisting of inside-out membrane vesicles catalyzed ATP-dependent Ca2+ accumulation. The creatine kinase ATP-regenerating system containing exogenous creatine kinase and phosphocreatine was most effective in supporting Ca2+ accumulation. The normalized rate of Ca2+ accumulation obtained by dividing the Ca2+ uptake rate by its initial equilibrium vesicular content was correlated with the (Na+ K+)-ATPase activity. The ATP-dependent Ca2+ uptake in sarcolemmal vesicles was inhibited by cardenolids--digitoxigenin and ouabain (40-50%), when the latter acted from inside the vesicles. The Ca2+ gradient formed in sarcolemmal vesicles at the expense of ATP was dissipated by Na+ but not by Li+ added into the external medium. The external sodium ions also caused Ca2+ efflux from sarcolemmal vesicles equilibrated with Ca2+. The described effects of Na+ are taken to show the existence of a Na-Ca exchange system in cardiac sarcolemma. Ca2+-ATPase of sarcoplasmic reticulum (SR) vesicles from guinea pig heart as well as ATP-dependent Ca2+ influx in these preparations were found to be partially suppressed by digitoxigenin. External NaCl led to be a rapid (during 5-10 sec) fall in vesicular Ca2+ content (by about 40%) accumulated at the expense of ATP followed by a return of Ca2+ content to its initial level. LiCl had no effect on Ca2+ content in SR. NaCl gradient directed inside the SR vesicles did not influence the distribution of Ca2+ between internal and external vesicular volumes in equilibrium (without ATP). The differences in properties of the Ca-pump of sarcolemma and sarcoplasmic reticulum found in this work support the idea on the existence of sarcolemmal system of ATP-dependent transport of Ca2+.

Exogenous phosphocreatine (PCr) and its cyclic analog, 3-phosphono-2-imino-1-methyl-4-oxoimidazolidine (PIMOI) were used as protectors of ischemic myocardium. PCr was insignificantly metabolized, whereas its analog was rapidly split, resulting in the formation of creatinine and inorganic phosphate as well as of minor amounts of PCr and creatine. Exogenous AMP and ATP accelerated PCr breakdown; in contrast, PIMOI hydrolysis slowed down in the presence of AMP. A similar inhibitory effect was observed after treatment of hearts with 2,4-dinitrofluorobenzene. These data together with those obtained for heart homogenates point to the enzymatic nature of PIMOI hydrolysis in ischemic heart. Acidic phosphatases and 5'-nucleotidases of the heart are supposed to be involved in this process.

The electron microscopic investigation has revealed in the body of the leech two types of vessels, that together with common signs possess a number of peculiarities in composition of endothelial cells. These vessels have different level of organization: the vessels of the first type, concerning the parenchyma of the leech, are nutritive, and the vessels of the second type combine capacitance and transport functions and are the place of hemolymph renovation at the expense of an active metabolic and synthetic activity of the endothelial cells. A fact is stated concerning a specific position of mitochondria in the endotheliocytes of the second type vessels: from the vessel's lumen they are not covered with plasmolemma along their whole extent and come into an immediate contact with hemolymph. Therefore, a hypothesis is suggested on functional activity of the endothelial cell mitochondria in the second type vessels. Presumptive differentiation of the two major vessels of the leech body makes it possible to suppose that there exist functional predecessors of the vessels of branchial and pulmonary type, that is vessels of lesser and greater circulation.

The effect of colchicine on the microcirculatory vessels of eye perilimbal area was revealed in 2 groups of experimental rabbits. Colchicine was found to promote the growth of capillaries both during intravenous injections of colchicine solution and during local colchicine application as an ointment. The proper substance of cornea was also changed under the influence of colchicine. Changes in the ultrastructure of the capillary wall and endothelial cells forming the capillaries have been noted.

The maximal content of mitochondrial isoenzyme of creatine kinase (CK) in rat heart mitochondria does not exceed 12.5 moles per mole of ATP-ADP translocase. This value was obtained by titration of mitochondrial CK activity in aged mitochondria by 5,5'-dithiobis-(2-nitrobenzoate) (DTNB) and 2,4-dinitrofluorobenzene (DNFB) and by a more complex and accurate method. The essential thiol groups of membrane-bound mitochondrial CK (and its enzymic activity) can be specifically protected by phosphocreatine (12 mM) + ADP (1-5 mM) against inactivation by DTNB. Mitochondria with protected SH-groups of CK and with groups inactivated by DTNB were repeatedly incubated with DTNB under identical conditions and the number of additionally reacted sulfhydryl groups and the changes in CK activity were measured. The differences in the number of additionally reacted SH-groups correlated with the changes in the CK activity, which made it possible to calculate the molar ratios of mitochondrial CK to cytochrome c oxidase and ATP-ADP translocase (2.16 +/- (0.4): 1:2, respectively).

The medial caudal artery, being a continuation of the aorta, ensures blood transport to all tissues of the caudal part of the dolphin body and its caudal fins. The branches of this artery are accompanied with some veins (complex vessels). In the microcirculatory bed there are many arteriolo-venulous anastomoses. The greatest attention of the author has been paid to the capillaries of the dermal pappilae which deeply penetrate into epidermis. It is possible to think that in this way: a) thermoregulation is improved; b) a greater hydroelastic effect is reached; c) epidermis blood supply is facilitated; d) certain conditions are created for synthesis of the dermal excretion.

On the basis of a previously proposed hypothesis about a spiral orientation of muscle elements in the walls of muscular arteries, terminal arteries and arterioles, as a universal regularity, concrete mechanisms of vascular biomechanics and bioregulation at hemodynamics are analyzed. The latter come to a cyclic change of the vasodilator phase into the vasoconstrictory one and vice versa, accompanying with a change of pressures in the local areas of the vessel from the lower to the higher and vice versa along the vascular length. Movement of the pulsed wave with the muscle elements is ensured by a consecutive change of pressures in successive local areas. This is performed under the influence of the blood stream pulsed wave and ensured by a multicontour regulatory system, including terminal and central, cholinergic and adrenergic reflectory arches, interacting in accordance with the principle of double reciprocal innervation and regulation.

It is shown that a cytosolic fraction of proteins from rat heart, containing all glycolytic enzymes and creatine phosphokinase (CPK) in natural proportions, catalyses in the presence of creatine (Cr) the intensive creatine phosphate (CP) synthesis coupled to glycolytic depletion of glucose, fructose-1,6-diphosphate (FDP) and phosphoenolpyruvate (PEP). The ratio of CP to lactate produced was 1.0 in the case of PEP as glycolytic substrates. In the CP production process the CPK reaction was not the rate limiting step: the mass action ratio for CPK was equal to the apparent equilibrium constant for this reaction, and the maximal rate of the CPK reaction exceeded the observed rate of glycolysis by a factor 6. It is concluded that in such a system the components of the CPK reaction are in quasiequilibrium and the mechanism of CP synthesis can be considered to be a continuous decrease in ADP concentration due to its phosphorylation in the glycolytic reactions, ATP concentration being constant due to its continuous utilization and resynthesis, this leading to an increase in CP concentration. The possible role of the CPK system in regulation of glycolysis in muscle cells is discussed.

The aim of the investigation has been to verify microscopical anatomy of the midbrain tegmentum (cytoarchitectonics of its reticular formation). A new modification of the silver impregnation technique has been used; it fully reveals multipolar neural cells with their numerous processes. The authors have succeeded in studying clusters of the neural cells between the oculomotor nerve nuclei and around them. This cluster differs from the surrounding neural tissue and from the oculomotor nerve nuclei by the cell arrangement density, by their size and form, as well as by the fact that it resembles the intramural vegetative neural plexus. The multiprocessing form of the cells of the intrategmental plexus and its topographic connection with the oculomotor nerve nuclei complex makes it possible to suggest an integrative function of this plexus in the system of the oculomotor nerve nuclei, ensuring the coordinative activity of the voluntary and involuntary muscles of the eye.

Vesicular preparations of sarcolemma isolated from rat myocardium possessed high ATPase (4.32 +/0 0.57 micromole/min per mg), adenylate cyclase (121 +/- 11 pmole/min per mg) and creatine kinase (1.74 +/- 0.35 micromole/min per mg) activities and a Na-Ca exchange activity specific for sodium. The ATPase activity was inhibited by digitoxigenin by 50-70% and was not changed by ouabain, EGTA, ionophore A23187 and oligomycin, thus showing the absence of mitochondrial and sarcoplasmic reticulum contaminations in the sarcolemmal preparations. The preparations consisted mostly of closed inside-out vesicles. The preparation was used to study the mechanism of Ca2+ penetration across the sarcolemmal membrane. For this purpose the vesicles were load with 45Ca2+, which relatively slowly diffused from the medium into the vesicles, and which was bound to the binding sites inside the vesicles (n = 20.5 +/- 4.6 nmoles per mg of protein, Kd approximately equal to 1.8 +/- 0.21 mM). The transmembrane movement of Ca2+ was demonstrated by the following findings: 1) the ionophore A23187 only insignificantly increased the total vesicular Ca2+ content, but strongly accelerated Ca2+ efflux from the vesicles along its concentration gradient; 2) gramicidin and osmotic shock caused a similar acceleration of Ca2+ efflux. Ca2+ efflux from these vesicles along Ca2+ concentration gradient was studied under conditions, when the extravesicular Ca2+ content was lowered due to its binding to EGTA and by dilution. The gradient of Ca2+ concentration was from 2.0 mM inside to approximately 0.1 micro M outside. The rate of 45Ca2+ efflux depended hyperbolically on the intravesicular Ca2+ efflux from the vesicles was inhibited by Mn2+, Co2+ and verapamil when they acted from the inside of the vesicles. An increase in ionophore A23187 concentration increased the efflux of Ca2+ hyperbolically and enhanced only the maximal rate of the efflux. It is concluded that the passive permeability of Ca2+ across the sarcolemmal membrane along its concentration gradient is controlled by Ca2+ binding to the membrane.

Investigation performed on topography, structure and resorptive function of lymphatic microvessels in the serous membranes gives possibilities to work out a model on formation and transport of lymph. Lymphatic postcapillaries (LP) - thin-walled endothelial channels with valves make an important link of the lymphatic system. The LP structure is similar to that of capillaries. These microvessels are situated in the interstitial space area, that are characterized with their high content of plasma proteins and water. Interrelation in concentrations of protein in the LP lumen and in the tissue ensures the existence of the osmotic gradient pressure through the wall and contributes liquor resorption into the lumen of microvessels. Peritoneal lymphatic capillaries are situated in the areas of a higher hydrotation level of the interstitial space. They can control the rate of the liquor filtration from plasma into tissue and regulate the resorption level in the whole lymphatic network. The model provides a differentiated participation of the LP and capillaries in performing resorption of proteins and liquor from the interstitium. The resorption mechanisms are closely connected with processes of the lymph movement along the vessels.

By means of impregnation of the microcirculatory bed vessels after V. V. Kupriyanov and transmissive electron microscopy, topological picture of hemomicrovessels has been estimated in the glomerular constructions of the dog mediastinal pleura. The composition of cell elements and peculiarities in distribution of the latter in the zone of the milk spots are examined. Their structural characteristics are manifested as presence of mesothelium of a decomplexated type accumulation of macrophagal and lymphocyto-plasma cells, glomerular organization of the capillary network and postcapillary venules, two types of endothelial lining of the metabolic microvessels. The role of the milk spots in ensuring immune protection, in migration of macrophages and in filtration of the pleural liquid is discussed.

The article claims that contractions of the cardiac left ventricle produce a whirling (turbulent) movement of blood that is maintained in the aorta. In the walls of large and small arteries, as well as in the arteriolar walls, myocytes have a spiral arrangement. Their contraction maintains the turbulent blood stream in the vessels with a small diameter, in spite of the fact that the Reinolds' number for them is rather small. The author considers that while making a mathematical analysis of the blood flowing in the arteries, it is necessary to take into account that the walls of the arterial vessels actively influence the blood stream.

Using 31P-NMR technique it was shown that exogenous phosphocreatine (10 mM) added in the cardioplegic solution provided higher levels of recovery of intracellular ATP (approx. 60% vs. 26% in the control) and phosphocreatine (90% vs. 43%) in perfused rat hearts after 35 min of total ischemia. Simultaneously significantly higher levels of contractile recovery (90% vs. 35%) and a three-fold decrease in creatine kinase release into the perfusate were observed. These effects of exogenous phosphocreatine can be related to either intracellular action of this compound or its interaction with cellular membrane.

Ultrastructural analysis on organization of the slug microvessel walls (arterioles, capillaries and venules) has been performed. Transport canals of endothelial cells in the capillaries and venules have been estimated. A conclusion is made that in the evolutionary process of development the vascular endothelium becomes more specialized.

The results of a complex functional-morphological analysis on the state of the mesentric microcirculatory bed have demonstrated a peculiar dynamics in increasing changes of its blood and lymphatic segments. Their degree depends on the stage of dehydration. On the 3d day, the changes revealed are not great and are of redistributive character. On the 6th day dehydration aquires the maximal intensity of changes in vessels and hemodynamics. By the 10th day, maximal level of vascular, intravascular and hemodynamic disorders is evident. Comparing these data and the results of investigations on intracellular and extracellular ion contents, it is possible to suggest a definite staged water elimination from the main depots of the organism. The reserves of extracellular water section are the first to be mobilized at the expense of its interstitial and transcellular links. On the 6th day of the experiment maximal intensity of blood and lymphatic dehydration is noted. Final stages of dehydration are characterized by a pronounced cellular dehydration.

Under regeneration of organs, wound healing, tumour growth, inflammatory processes, under many compensatory and adaptive reactions in the organism of mature persons and animals, an inevitable formation of new blood vessels (neovasculogenesis) takes place. Modern notions on mechanisms of neovasculogenesis are based on the fact that new formation of vessels in a mature organism includes processes of migration and replication of endothelial cells according to the principle: "endothelium from endothelium". The literature data on neovasculogenesis in the mature organism are summarized and compared with the authors' investigations. Characterization of new blood vessels growth is presented; ultrastructural organization of endotheliocytes in growing capillaries, formation of barrier-transport properties in the newly formed vessels, role of inductors and inhibitors of neovasculogenesis in creation of new vascular formations are considered.

Unidirectional fluxes from ATP to phosphocreatine (PCr) catalyzed by MM-isoenzyme of creatine kinase (CK) were measured by using 31P-NMR saturation transfer technique and by means of radioactively labeled [gamma-32P]ATP. At 30-37 degrees C and pH 7.4 in a wide range of [PCr]/[creatine] ([PCr]/[Cr]) ratios (0.2 to 3.0) both of these methods gave similar results, thus showing that magnetization (saturation) transfer allows to determine fluxes close to real ones under "physiological" conditions. However, at [PCr]/[Cr] ratio higher than 5 ([ADP] less than 30 microM) or at decreased temperatures (7-15 degrees C, [PCr]/[Cr] approximately 1) fluxes determined by saturation transfer substantially exceeded those measured with the radioactive label. These data imply that under "physiological" conditions phosphoryl group transfer is actually rate-determining step of the CK reaction. On the contrary, at high [PCr]/[Cr] values or at low temperature the control step could be shifted from the phosphoryl group transfer or distributed among other steps of the reaction.

The work describes the results of complex investigation of the state of the supporting-motor apparatus of extremities of dogs subjected to six-month-long restriction of motor activity and the following reparation during a month. Intravital rentgenological, anatomical, histochemical and electron microscopic methods were used. It was shown that continuous hypokinesia resulted in substantial alterations of the vascular bed in the macro-micro-ultrastructural level, disturbance of metabolism, focal reconstruction of tissues of the extremities by the type of natural death of ultrastructural elements without a following reparation. A one-month term appeared to be insufficient for reparation of structural disorders. Special attention was given to reactions of the vascular system. Signs of blood transport via extracapillary pathways from the arterial bed into the venous bed were noted.