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The results of the diagnosis of cognitive impairments in patients with endocrinological and cardiological profiles are presented. The Montreal MoCA test was used to assess cognitive functions.

Objective: to study the possibility of applying electro-optical analysis for the assessment of cell viability of tularemia microbe vaccine strain at different stages of experimental live tularemia vaccine production.Materials and methods. The research object was a cell culture of Francisella tularensis 15 NIIEG. Investigations were carried out at all stages of experimental live tularemia vaccine (ELTV) manufacturing according to an advanced technology: cultivation, concentrating, diafiltration, mixing with drying media, stabilization, and storage (two-year period of observation). Electro-optical analysis by the parameter “polarizability anisotropy” of bacterial cell was conducted with the help of EloTrace (EloSystems, Germany). Total concentration of cells was evaluated using density metering at 590 nm and spectrometry – at 650 nm. Viability was assessed through inoculation of plates with FT-agar.Results and discussion. The experiment has demonstrated that the change in polarizability anisotropy of the cell at the frequencies of 900 kHz and 2100 kHz, reflecting the state of cytoplasm and cytoplasmic membrane, respectively, is the earliest response to changes in vital indicators of bacterial culture in the process of cultivation. Thereby, the decrease in viability of F. tularensis cells occurrs well before the decrease in cell concentration. We have shown the preservation of viability of F. tularensis 15 NIIEG cells at all stages of experimental live tularemia vaccine production. Electro-optical analysis allows for registering the changes in vital parameters of microorganism cells in real-time mode, while the assessment of viability applying bacteriological method takes up to 5 days. Different stages of tularemia vaccine manufacturing have impact on the vital indicators of F. tularensis cells, and electro-optical analysis is a prospect method of control of such parameter as “Specific activity (the number of live microbial cells)”.

Current areal of anthrax among live stock and wild animals covers almost all the continents. The cause of human infection is conventionally considered to be the contact with diseased animals in the process of carrying for an animal, forced slaughter or further trimming of carcasses, as well as contact with infected raw materials of animal origin. Licensed vaccines has made an invaluable contribution to the improvement of epidemiological situation on anthrax, however, development of the vaccines complying with current scientific progress remains relevant. We have constructed a vaccine prototype containing recombinant protective antigen and S-layer EA1 protein and added state-of-the-art CpG 2006 adjuvant to the formulation. We have demonstrated the advantage of the lyophilized form of the preparation. Objective — obtainment of anthrax vaccine prototype in lyophilized state and assessment of the prototype compliance with the requirements to vaccine preparations. Materials and methods. Isolation of rPA and EA1 protein was carried out using producer-strain B. anthracis 55ΔTПА-1Spo– on an integrated end-to-end manufacturing line, including concentration, diafiltration and two-phase chromatography. CpG 2006 adjuvant was synthesized according to known sequences. Components were mixed and lyophilized in sublimation unit. Combination of 1% sucrose and 3% glycine was used as cryoprotector. Effectiveness and safety of the preparation were evaluated on the model of BALB/c mice and guinea pigs applying immunological, morphometric, and histological assays. Antibody titers in sera of immunized animals were evaluated using standard ELISA procedures. Protective properties were investigated through LD50 values for the test-strain used on immunized and control animals and immunity index. Results. We have performed complex investigation of the anthrax vaccine prototype, containing B. anthracis 55ΔTПА-1Spo– proteins as main and supplementary antigens, as well as CpG 2006 adjuvant, stabilizers and preservative agent. The prototype meets the requirements to immunobiological medicinal drugs by all physical-chemical properties. Our preparation does not have a toxic effect on the organism of laboratory animals in case of subcutaneous and intraperitoneal administration of single human dose. Pathomorphological study of guinea pigs’ organs immunized with double dose of the vaccine prototype has not revealed any evidence of damaging effect on the cells and tissues of macroorganism. The prototype protects BALB/c mice from the infection with B. anthracis 71/12 test-strain.

Although the search of inhibitors of the key enzymes of HIV replication has remained a topical and intensively studied topic over the last several decades, potential inhibitors of the enzymes bearing thiocyano groups have been little studied. In this work, we tried to synthesize polymethylene derivatives of nucleic bases bearing thiocyano groups at the ω-position of the polymethylene chain. The reaction of new alkylating reagents, methyl α-thiocyano-ω-chloroalkanoates, with nucleic bases led to a complicated and barely separated product mixture. The only exceptions were the reactions of uracil or thymine with methyl 2-thiocyano- 2-chloropentanoate, in which 2-(N 1-uracilyl or -thyminyl)tetrahydrothiophene-2-carboxylates were isolated in 45–50% yields. The potential mechanism of the reaction is discussed.

Objective of the study is to experimentally substantiate the possibility of production of anti-cholera immune-enterosorbent in the pharmaceutical form of a pill. Materials and methods : experimental antitoxic immune-enterosorbent against cholera, stabilized using cool dehumidification. Residual moisture of enterosorbent lyophilizate was determined by means of Sartorius MA 150 moisture meter. Screen assay of the powders and granulates was performed applying the sieving of bulk material samples through screen set with sieve openings of various sizes. Specification of tap density was carried out with the help of SVM-10 unit. Granulation of specific enterosorbent was done using GPCG 2 LabSystem. The pills were manufactured in tablet press, MiniTabT. The hardness of the pallets was carried out by means of TBH 125 TD tester. The test for friability of the pills was performed in GTA 120. Results and conclusions. Utilization of cellulose microcrystalline and polyvinyl pyrolidone as pharmaceutical aids for granulation of lactose monohydrate is experimentally substantiated. It is established that the obtained granulate with passable values of technological parameters can serve as the basis for pharmaceutical dosage form of specific enterosorbent. Identified has been optimum mass of anti-cholera enterosorbent tablet cores. Demonstrated has been the possibility of Acryl-eze enteric coating application as protective shell of the pills. Studied has been specific activity of the pelleted enterosorbent in vitro, verified is its resistance capacity under conditions modeling gastrointestinal tract. In consequence of the performed trials and tests, technology for the production of antitoxic enterosorbent against cholera – enteric-coated tablet – has been developed. Long-term trials: the storage of the constructed preparation at 4–8°C within 24 months period (the observation time) – have revealed retention of enterosorbent activity, which testifies to its stability and defined the shelf life of specific tableted anti-cholera immune-enterosorbent.

Objective of the study is experimental substantiation of possibility to produce new presentation form of cholera diagnostic sera – lyophilizate in bottles. Materials and methods. Cholera diagnostic sera. Liophylization was performed in Martin Christ Epsilon 2-6D. Residual moisture of dry sera was determined using humidity meter Sartorius MA 150. Solubility of experimental samples was assessed visually. pH was evaluated by potentiometry with the help of PK SevenExcellence-475 Mettler Toledo device, measuring pH/ORP/Ion content/conductivity/concentration. Specific activity and specificity was analyzed through expanded agglutination reaction, using relevant control strains of cholera vibrio. Results and conclusions. Experimentally justified is the possibility to lyophilize cholera diagnostic sera in flasks. Specified are the optimum parameters of lyophilization. It is determined that lyophilization does not result in deterioration of properties, as judging by the quality indicators they meet the requirements of regulatory documentation. Using accelerated aging test, it is demonstrated that the new presentation form of cholera diagnostic sera – lyophilizate in flasks – maintains their specific activity within five years term (the set out shelf life), which fully conform to normative standards.

Objective of the study was to develop and test new biotechnological approaches for live tularemia vaccine production. Materials and methods: Francisella tularensis 15 NIIEG strain was used as producer-strain; Francisella tularensis 503 strain – as test infecting one. Producer strain was cultivated on solid and liquid nutrient media. Tangential ultrafiltration was performed with the help of microfiltration module “Viva-flow”. Lyophilization was conducted using drying installation – Free Zone 2.5 L. Results and discussion: Application of the designed liquid nutrient medium on the basis of enzymatic fibrin hydrolysate and submerged cultivation of the producer-strain has allowed for a significant biomass yield increment. At the stage of tularemia microbe culture concentration via microfiltration through filtering membranes with pore size of 0.2 μm, in the mode of tangential liquid flow, increased has been the content of microbe cells; the nutrient media residues – removed. Comparative analysis of the obtained in accordance with experimental technique laboratory series of the vaccine and commercial preparation of live tularemia vaccine has demonstrated their conformity with the specific normative properties. It is established that application of modified liquid nutrient medium, submerged cultivation conditions, methods of biomass concentration and separation has no negative influence on the main properties of live tularemia vaccine and will provide for considerable produce-ability increase in the future.

The review provides information on the major outcomes of research and development work, performed within the frames of the Federal Target Program “National system of chemical and biological safety” (2009-2014), aimed at elaboration and introduction of cultural techniques into the manufacturing of anti-rabies immunoglobulin. Described are the key phases in methodology engineering, deployed for the large-scale cultivation of fixed rabies virus, concentration of cultural liquid, quantitation of rabies virus using PCR, and immunization of producers. Obtained pilot batches of the enhanced anti-rabies immunoglobulin, complying with normative requirements to commercial formulations, testify to the effectiveness of the developed biotechnological and methodological procedures, as well as of the designed engineering-manufacturing project documentation.

Objective of the study was to substantiate experimentally the possibility to enhance efficiency of manufacturing process through application of novel engineering solutions in the course of freeze-drying of vaccine immunogens. Materials and methods. Choleragen-anatoxin and O-antigens, Inaba and Ogawa, served as specific immunogenic components of the vaccine. Identified were temperature values for O-antigen eutectics (approx. -35 oC). At reaching -55 oC choleragen-anatoxin froze incompletely (fractionally). Full solidification of the preparation was achieved by means of the “annealing”. Revealed was non-effect of the tested freeze modes on the properties of antigen components of chemical cholera vaccine. Desired values of technological parameters for primary drying and desorption were specified by trial. Investigations of activity of chemical cholera vaccine immunogen lyophilizates testified to the compliance with the rated critical requirements. Results and conclusions. Results of the study provided for significant time expenditure reduction and obtainment of high-quality preparations at once.

Experimentally substantiated is the possibility to apply tangential ultrafiltration for desalting antigen components of the tableted bivalent chemical cholera vaccine. Specified are the technological parameters of the process. It is demonstrated that the properties of choleragen-anatoxin (produced by Vibrio cholerae strain 569B Inaba) and O-antigens (produced from V. cholerae 569B Inaba and M-41 Ogawa strains) obtained using the designed methodology are as efficient as the ones manufactured using certified procedure and satisfy regulatory requirements. Experimentally substantiated technology for the desalting of antigen components of chemical cholera vaccine provides for the reduction of the time elapsed up to 5-6 hours from the original 3 to 4 days. It also allows for the manufacturing under controlled conditions. This hard-ware controlled method of desalting has been implemented into the vaccine production practice.

Consideration is given to implementation of state-of-the-art filtration technologies for up-scaled manufacturing of cholera toxin B-subunit, produced by recombinant Vibrio cholerae non O1 KM93 strain. Selected are micro- and ultra-filtration membranes to be incorporated into manufacturing method. Investigated are the properties of cholera toxin B-subunit, obtained applying the pilot technology. The engineered method for up-scaled manufacturing of cholera toxin B-subunit makes the procedure easier-to-maintain due to tangential micro- and ultra-filtration, performed at the stage of purification and concentration. It excludes labor-consuming chromatographic purification, while retaining B-subunit properties. The studies undertaken make it possible to manufacture cholera toxin B-subunit with the same characteristics as in the case of the pilot technology, but under production conditions, and use it as a component for chemical cholera vaccine.

Presented is mathematical model of kinetics of the process of O-antigen and cholera toxin synthesis during periodical submerged cultivation of V. cholerae 569В Inaba with limitation as regards carbonic substrate. The proposed model is based upon analysis of experimental data on V. cholerae 569В Inaba biomass and antigens accumulation, rate of growth and antigens release, and glucose utilization. Using Mathcad 15.0 software calculated are coefficients of differential equations entering into the mathematical model. Comparison of predicted and experimental data demonstrates that relative error of determination of concentrations of the synthesized substances, glucose and cholera vibrio is between 5 and 20 %. The proposed model permits to determine maximum output of final products and specify the parameters of cultivation process performance at different initial conditions.

Displayed is the review of domestic and foreign literature sources devoted to matters of cholera vibrio cultivation. Discussed is the information concerning the following methods utilized in the technological process of vibrio growth stimulation: batch cultivation, fed-batch, fermentation and dialysis, periodic and continuous cultivation. Analyzed is the impact of such parameters as dissolved oxygen concentration, count of carbon nutrition source, medium pH, temperature rate , concentration and physiological condition of inoculate, duration of technological process, affecting the growth of this microorganism and synthesis of its antigens. Consequently, literature data analysis has contributed to the selection of proper method for cholera vibrio cultivation and consideration of the factors mentioned above for the development of manufacture technology applied to the production of medical immunoglobulin preparations for diagnostics and prophylaxis of cholera.

Studied is the kinetics of major antigen accumulation at growing of Vibrio cholerae M-41 Ogawa and 569 B Inaba strains in industrial and engineered reactors. Demonstrated is the possibility to obtain conditional native protective antigens in the engineered bioreactor. Shown is the identity of physiological and morphological properties of industrial Vibrio cholerae strains during their submerged cultivation in industrial and engineered bioreactors. Cholera bivalent chemical vaccine obtained using engineered bioreactor possesses quality indices meeting the requirements of normative documents and equal to those of preparation received by traditional approach.

Nonstructural protein 3 (NS3) of hepatitis C virus plays a key role in the functioning of the virus. NS3 displays three enzymatic activities, namely, protease activity associated with the N-terminal domain, coupled nucleoside triphosphotase (NTPase), and helicase activities, localized to the C-terminal domain. In this work, we studied the effects of various polymethylene derivatives of nucleic bases on the NTPase (by the example of ATPase) and helicase activities of NS3. It was demonstrated that some tested compounds inhibited NS3 helicase activity; however, a considerable part of the compounds activated the NTPase activity of NS3 and several other proteins displaying NTPase or selective ATPase activity. Such ATPase activators have not been earlier described, suggesting an unusual activation mechanism. The activation ability of the tested compounds depended on the ratio of substrate (ATP) and activator concentrations, and reached its maximum at a 1000-fold excess of the substrate. A mechanism of ATPase activation was proposed to explain the observed effects.

The aim of the study was to estimate the dynamics of respiratory system clinicofunctional scores among patients with COPD at the health resort Belokhuriha. There were examined 188 cases of mild and middle-severe COPD. All the patients received different rehabilitation complexes in the conditions of health resort Belokuriha’s climate-recreational zone against the background of which there was conducted an estimation of the respiratory system clinicofunctional scores and depending on the applied methods there was evaluated its efficiency. In the process of the group rehabilitation where physical exercises were included there was recorded the dynamics of the main symptoms — decrease of the manifestation degree of dyspnea, cough, sputum discharge and scores of the respiratory system functional tests. OFV1 has reliably increased only in the group where clipping massage, exercises in the counter-resistance mode for the respiratory muscles and the terrainkur were used. The use of physical exercises in the rehabilitation of patients with COPD improves clinicofunctional scores of the respiratory system and its efficiency.

The dynamics of in vitro development of reconstructed bovine embryos activated at various time after electrofusion was studied. The in vitro mature oocytes without zona pellucida enucleated using the blind method were taken as cytoplasts. Fetal fibroblasts were used as the nuclei source. Approximately 40% of embryos activated between 3 and 3.2 hours after electrofusion developed to blastocysts. The efficiency of in vitro development of cloned embryo of cloned embryo did not decrease when the time between electrofusion and activation was extended up to 4–5 hours. The pattern of more successful development of in vitro reconstructed embryos was found using enucleated oocytes, extrusion the first polar body to 18 hours in comparison with oocytes matured in vitro afterwards, as cytoplasts.

Developed is the system of differential equations that characterize kinetics of biomass growth, glucose utilization and O-antigen accumulation in the process of submerged cultivation of V. cholerae strain M-41 Ogawa. The parameters of the mathematic model are identified. Using the developed software in Mathcad 15.0 determined are kinetic constants and coefficients. The mathematical model is demonstrated to describe adequately O-antigen biosynthesis process. The received data can be used in large-scale technology of V. cholerae strain M-41 submerged cultivation.

We studied the effects of nicotine and cytisine injected i.p. in equimolar doses (0.5 μmol/kg) on the formation and extinction of the conditioned active avoidance reflex (AAR) in rats; a combination of conditioning acoustic stimulation and unconditioned nociceptive electrocutaneous stimulation was used for training. A stable AAR was formed more rapidly in the case of nicotine injections; the corresponding effect of cytisine injections did not attain a significance level (probably because of the weak effect of this cholinomimetic on AAR formation in slowly trained animals present in the tested group). Injections of both nicotine and cytisine in the course of formation of a stable AAR led to a significantly slower extinction of the conditioned reflex habit. Both cholinomimetics demonstrated such an effect with respect to both the entire animal population and rats with rapid extinction of the habit. Cytisine-induced slowing down of extinction of the AAR was more significant than the corresponding effect of nicotine. We postulate that the positive effects of cytisine and nicotine on maintenance of the AAR are mediated by activation of neuronal nicotine cholinoreceptors having the α3β4 subunit structure.

Worked out is the experimental technology for protective antigens of Vibrio cholerae 569 B Inaba (cholera-anatoxin and O-antigen) concentrating by means of tangential ultrafiltration. Optimization of concentrating technological process is carried out. This technique makes it possible to obtain cholera vaccine components meeting all regulatory requirements.

Demonstrated is possibility to apply cross-flow ultrafiltration method for O antigen of Vibrio cholerae M-41 Ogawa concentrating from germ-free centrifugate. Technological process of concentrating was optimized. Worked out were the regimes of conservation and cleaning of the ultrafiltration device. The prospects of cross-flow ultrafiltration method introduction in technology of cholera chemical bivalent vaccine production were determined.

This review considers activation of synaptic receptors (SR) as a process of transduction of the energy of interaction between an agonist (A) and an agonist-recognizing module (R) toward an ion-conducting module (channel,Ch) orG protein within respective complexes (ARCh orARG). The agonist provides functional and, in the case of metabotropic SR, spatial association of protein components in these complexes. Conformational transformations of the latter, which are sufficient for dissociation ofG protein into subunits or opening of an ion-conducting channel, sometimes need additional energy expenditure. The source for this energy can be interaction with one more ligand: guanosine-5′-triphosphate (in the case of metabotropic SR) or glycine (in case of NMDA receptors), which act as co-agonists. The activation of SR is regulated by their allosteric modulators, which affect either the kinetics of interaction between the agonist and receptor by changing the rate of dissociation with the agonist or the kinetics of conformational transitions of the components into the activated or desensitized state.

SUMMARY 1. A whole-cell patch-clamp study of the effects of ambocarb, a novel nootropic β-carboline, on sodium currents in rat acutely isolated hippocampal pyramidal neurons was performed. 2. Ambocarb potently and reversibly suppressed sodium currents in a concentration range of 3–300 μmol/L. The amount of block was dependent on the holding potential, with half- maximal inhibition values being 26 and 94 μmol/L at –80 and –120 mV, respectively. 3. Ambocarb induced a hyperpolarizing shift in the steady state availability curve, which indicates an increase in the proportion of inactivated sodium channels. This action is presumably mediated by promoting the development of inactivation and slowing the recovery of sodium channels from inactivation. 4. Because many neuroprotective drugs were shown to inhibit sodium currents, down-modulation of voltage-operated sodium channels that complements the known positive interaction of ambocarb and other related β-carbolines with GABAA receptors may provide a promising strategy in the treatment of brain disorders associated with trauma and ischaemia.

Bovine embryos are reconstructed with the use of fetal fibroblasts as donors of nuclei and enucleated oocytes without the zona pellucida as recipients. The stages of electrofusion and in vitro culturing of embryos without the zone pellucida up to the blastocyst stage is perfected.

Experiments on superfused slices of rat hippocampus showed that the nootropic drugs pyracetam, ethymizol, ambocarb, and nooglutil increase the amplitude of populational EPSP (pEPSP) of neurons of the dentate gyrus evoked by electrical stimulation of the perforant pathway (PP). Nootropes exert no effect on the process of presynaptic glutamate liberation from the PP axons, but increase the chemosensitivity of the postsynaptic AMPA/kainate receptors mediating EPSP generation in the dentate gyrus neurons. Inhibitors of protein kinase (A-buthamide) and guanylatecyclase (methylene blue) do not modify the effects of nootropes. The nootrope-induced potentiation of pEPSP does not develop against the background of the application of calmodulin inhibitor W-7. In the presence of protein kinase inhibitor C, polymixin B, nootropes reversibly depress pEPSP in the dentate gyrus neurons. Blocking of the NMDA receptor ionic channels by ketamine and of the voltage-dependent T-type calcium channels by Ni2+ does not significantly modify the effects of nootropic drugs. A blocker of Ca2+-ATPase of the Ca2+ stores sodium orthovanadate, potentiates the effects of nootropes. Dantrolene, which disrupts Ca2+ liberation from the non-mitochondrical depots, blocks the effects of nootropes and diminishes pEPSP depression evoked by nootropes in the presence of polymixin B. On the basis of presented data, it is supposed that nootropic drugs assist Ca2+ liberation from the neuronal depots and activate calmodulin-dependent protein kinase and protein kinase C. Protein kinases phosphorylate the intracellular domains of the AMPA/kainate receptors, and this process results in an increase in their sensitivity to excitatory amino acids.

Application of serotonin (5-hydroxytryptamine; 5-HT) to rat dorsal root ganglion neurons under conditions in which potassium conductance was blocked by cesium ions elicited depolarizing responses followed by an increase in membrane conductance. The responses did not exhibit desensitization and were due to activation of 5-HT receptors of the third type (5-HT3Rs), since they were insensitive to methysergide, the 5-HT2R antagonist, but were inhibited by tropicetrone (ISC 205–930) and metoclopramide, the 5-HT3R antagonists. The reversal potential of the 5-HT-induced depolarizing responses was −11.9 mV; their amplitude decreased following a decrease in extracellular Na+ concentration but remained constant after intracellular injection of GTP. The amplitude of the responses increased following elevation of intracellular cAMP concentration caused by theophylline or sodium fluoride whose potentiating effect was reduced by butamide, a protein kinase A inhibitor. Potentiation of the 5-HT-induced responses was also produced by increased intracellular Ca2+ concentration following either direct intracellular injections or a burst of action potentials. The potentiation could be prevented by trifluoroperazine, the calmodulin inhibitor. The 5-HT effects were also potentiated by methylfurmetide, an activator of muscarinic acetylcholine receptors. The effect of methylfurmetide was slightly decreased by trifluoroperazine and was markedly decreased by polymixin B, a protein kinase C inhibitor. The effects of 5-HT were also enhanced by ethanol.

We investigated the effect of monoamines and their agonists and antagonists upon responses of motoneurons medicated by NMDA-glutamate receptors. It was found that adrenalin strengthens the responses studied through activation of α-and β-adrenoreceptors. This effect of adrenalin is suppressed by an α-adrenoblocker (phentolamine) and a β-adrenoblocker (propranolol); it is restored by an α-adrenomimetic (phenylephrine hydrochloride) and a β-adrenomimetic (neoepinephrine). In 66% of the cases, dopamine inhibited motoneurons responses; in 34% of the cases, it strengthened such responses. In the presence of a selective blocker of D2-dopamine receptors (sulpiride), it only strengthened motoneuron responses. Serotonin strengthens responses of motoneurons; its action is suppressed by a blocker of type-II serotonin receptors (dezeril). A selective agonist of subtype-1A serotonin receptors, campirone, suppresses motoneuron responses. The effect of campirone is weakened by propranolol. The strengthening of NMDA-responses of motoneurons evoked by neoepinephrine and dopamine in the presence of sulpiride is weakened by a blocker of cAMP-dependent protein kinase, tolbutamide, and the strengthening of responses by phenylephrine hydrochloride and serotonin is weakened by an inhibitor of calmodulin, trifluoroperazine.

We studied the dynamics of in vitro maturation of bovine oocytes, the efficiency of asynchronously matured oocytes as recipients for the generation of embryos produced by nuclear transfer, and the potential for using blind enucleation of zona-free bovine oocytes in bovine cloning. At 15 h after the initiation of maturation (hpm), oocytes were freed from both cumulus cells and the zona pellucida, and the dynamics of oocyte maturation were monitored every 30 min through the criterion of extrusion of the first polar body (PB1). More than 41% of bovine oocytes had extruded PB1 by 16.5 hpm, and were designated as representing a group of rapidly maturing oocytes. A second group, comprising about 25% of all oocytes, had extruded PB1 by 18.5-20.0 hpm. Examination of Hoechst 33342-stained samples demonstrated that PB1 on the surfaces of zona-free bovine oocytes were always located near the maternal chromosomes. Zona-free oocytes were enucleated by removing PB1 and about 3% of the adjacent oocyte cytoplasm without chromatin staining. Successful enucleation of zona-free bovine oocytes was achieved in 96.9% of cases. The rate of development to the blastocyst stage was significantly greater in embryos reconstructed from rapidly maturing oocytes (47.8%) than with oocytes maturing at 18.0-20.0 hpm (33.3%). Overall, two large groups of bovine oocytes could be distinguished during in vitro maturation by the time required to reach the second stage of metaphase. Bovine embryos reconstructed from rapidly maturing enucleated oocytes had a significantly greater rate of development to the blastocyst stage than did embryos derived from later-maturing oocytes. We conclude that blind enucleation is a simple and efficient method for preparing cytoplasts in zona-free bovine cloning.

Tryptamine has been studied for its effect on the 5-hydroxytryptamine-induced responses of the dorsal root ganglion neurons in rat with intracellular registration of the membrane potential and conductance and application of drugs from micropipettes under pressure. It was found that tryptamine applied in high concentrations acted like 5-hydroxytryptamine; but in the concentration range when it has no effect on the membrane potential and membrane conductance it either enhanced (10(-7) mol/l) or diminished (10(-5) mol/l) 5-hydroxytryptamine responses mediated by 5-HT1A- but not by 5-HT2-receptors. Harmane acted like tryptamine, but its derivatives either only enhanced or only inhibited the 5-hydroxytryptamine effects. The allosterical nature of 5-hydroxytryptamine-modulating action of tryptamine, harmane and its derivatives is discussed.

Dopamine and phenylephrine lower the tone of the smooth muscles of isolated strips of rat stomach in concentrations of 10−6M or more. The concentration-effect curves have the same slope. The effect of dopamine is unchanged in the presence of propranolol (5·10−6 g⩳). Phentolamine (and also dihydroergotamine and tropaphen) exhibits equal antagonism to phenylephrine and dopamine. It is concluded that dopamine and phenylephrine relax the smooth muscles of the stomach by their action on α adrenoreceptors. The latter differ from the α adrenoreceptors of the vas deferens (rats) in their high sensitivity to the blocking effect of certain neuroleptics, namely haloperidol, trifluoroperazine, and chlorpromazine, pA2 for which (8.11–8.64) is of the same order as pA2 for α adrenolytics (7.76–8.46). The similarity and difference between α adrenoreceptors of muscles of the gastrointestinal tract and inhibitory dopaminergic receptors of nerve cells are discussed.

Experiments on superfused isolated spinal cord preparations from rats aged 8–13 days showed that noradrenal in and serotonin have only a weak effect on monosynaptic reflex discharges but a substantial effect on polysynaptic motoneuronal discharges: noradrenalin potentiates whereas serotonin inhibits them. Both amines inhibit dorsal root potentials evoked by stimulation of high-threshold afferents. Potentiation of polysynaptic motoneuronal discharges induced by noradrenalin is connected with hyperpolarization of high-threshold afferents due to inhibition of the function of neurons in the substantia gelatinosa, and with increased excitability of interneurons participating in the generation of motoneuronal discharges. Serotonin inhibits polysynaptic motoneuronal discharges through its direct depolarizing effect on terminals of high-threshold afferents and depression of interneuron activity responsible for these discharges. Adrenergic and serotonin receptors, mediating these effects of noradrenalin and serotonin, were subjected to pharmacologic analysis.

Serotonin causes contraction of the smooth muscles of the vas deferens and of a strip of stomach from rats by its action on D-serotonin receptors. Only a small part (about 10–14%) of its contractile effect is due to liberation of endogenous catecholamines. The action of serotonin on a strip of rat stomach is accompanied by increased entry of isotropes45Ca and22Na into its cell. The change of direction of the curve of concentration versus effect of serotonin on the strip of stomach is due to accumulation of sodium ions in the cells.

Superfusion of isolated hemisected spinal cords of 9-13-day old rats with noradrenalin (NA) solution depolarized or hyperpolarized the motoneurons depending on the NA concentration. Both effects were the result of the direct action of NA on the motoneurons, for they were given in medium containing an excess of Mg and deficiency of Ca ions.a-Adrenoblockers depressed both the depolarizing and hyperpolarizing effects of NA. The depolarizing effect of dopamine on motoneurons was abolished in medium containing excess of Mg ions. Its direct hyperpolarizing action of motoneurons was suppressed by haloperidol but unchanged by phentolamine. The depolarizing effect of serotonin and its metabolites — mexamine, kynurenine, and 3-hydroxy-anthranilic acid — persisted in the presence of an excess of Mg and deficiency of Ca ions, but it was suppressed by deseryl (methysergide) and the benzyl analog of serotonin. The hyperpolarizing effect of serotonin at high concentrations (10−4–10−3 M), revealed in some experiments, was abolished in medium containing excess of magnesium ions in the presence of morphine.

In experiments on isolated spinal cord of young rats 7–14 days old under conditions of takeoff of the electrical activity of the spinal roots with a sugar bridge, it was established that the GABA-mimetic phenibut induces direct depolarization of the motoneurons. In the same concentration range (10−5-10−4 M), GABA has a dual effect. The depolarizing component of the action of GABA in part of the experiments and the depolarizing effect of phenibut in all the experiments are preserved in the presence of picrotoxin (10−5 M) and under conditions of superfusion of the brain with a solution with a reduced chloride concentration. This depolarizing effect of phenibut, not associated with the activation of GABAA receptors and chloride channels coupled with them, is unchanged in a medium with Na+ deficiency, is enhanced during depolarization of the motoneurons due to an increased concentration of K+ (10 mM) and in the presence of imidazole, but is entirely eliminated in a medium with Ca2+ deficiency, containing 2 mM Mn2+, or in the presence of theophylline (10−4 M). It is suggested that phenibut, and to some degree, GABA lower the intracellular concentration of cAMP by means of activation of the GABAB receptors, which leads to blocking of the functional activity of the potential-dependent calcium channels and a decrease in the calcium-activated outflowing potassium currents. The ability to weaken the inflowing calcium currents may also be the basis of the presynaptic inhibiting effect of GABA and GABA-mimetics (phenibut, baclofen, etc.) on the pulsed release of mediators by the axon terminals of catecholaminergic, glutamatergic, and GABA-ergic neurons.

Experiments on an isolated spinal cord of 8-15-day-old rats have shown that one of the possible mechanisms of the GABA-potentiating action of the benzodiazepine tranquilizer, chlorodiazepoxide, may be a decrease in the intraneuronal concentration of Ca2+. This is evidenced by the enhancement of the GABA-potentiating action of chlorodiazepoxide under Ca2+ deficiency in the medium and in the presence of the blockers of the voltage-dependent Ca2+ ionic channels--Mn2+ and Co2+, and by the reduction of the effect in question under Ca2+ excess in the medium and in the presence of the K+ channels blockers--tetraethylammonium and 4-aminopyridine. The GABA-potentiating action of harmane is likely to be related to the blockade of the voltage-dependent K+ channels and elevation of the intracellular concentration of Ca2+.