Vol 162, No 5 (2017)

We studied the effect of extracellular purine nucleotides (NAD⁺ and ATP) on spontaneous arrhythmogenic activity caused by norepinephrine in myocardial sleeves of pulmonary veins. In pulmonary veins, NAD⁺ and ATP reduced the frequency of action potentials and their duration at regular type of spontaneous activity caused by norepinephrine. NAD⁺ and ATP lengthened the intervals between spike bursts at periodic (burst) type of spontaneous activity. In addition, ATP shortened the duration of spike bursts and the number of action potentials in the “bursts” caused by norepinephrine in the pulmonary veins. It was hypothesized that NAD⁺ and ATP attenuate the effects of sympathetic stimulation and when released together with norepinephrine from sympathetic endings in vivo, probably, reduce arrhythmogenic activity in myocardial sleeves of pulmonary veins.

Characteristics of depressive-like behavior of male rats with androgen deficiency born by mothers subjected to prenatal stress during pregnancy were assessed by using Porsolt tests and open-field tests. The level of depression-like behavior in prenatally stressed males increased more intensively than in non-stressed gonadectomized males. Chronic administration of testosterone propionate (0.5 mg/kg, intramuscularly, for 14 days) increased depressive behavior in prenatally stressed gonadectomized males in contrast to its antidepressant effect in nonstressed gonadectomized rats. Prenatal stress considerably exacerbated depressive behavior of male rats under conditions of androgen deficiency and abolished the antidepressant effect of exogenously administered testosterone propionate.

We studied the role of purinergic P₂X receptors in the body response to cooling. In experiments on rats, P₂X receptor antagonist PPADS was administered in different modes, which resulted in changes of different characteristics of the thermoregulatory response to cold. Iontophoresis of P₂X antagonist into the skin decreased the thermal thresholds of all thermoregulatory responses to cooling, which can attest to a modulating effect of P₂X receptors on peripheral thermosensitive afferents. Intraperitoneal administration of P₂X antagonist suppressed thermoregulatory activity of skeletal muscles (shivering) developing during cooling without changing the thresholds of thermoregulatory responses. The findings suggest that ATP and P₂X receptors play an important role in the formation of the response to cooling.

We studied association of single nucleotide polymorphism Glu298Asp (rs1799983) of the NOS3 gene with the risk of metabolic syndrome in the Slavic population. Blood samples were obtained from 128 patients with metabolic syndrome and 100 healthy individuals. Polymorphism Glu298Asp of the NOS3 gene was genotyped by allele-specific PCR. Allele Asp (OR=1.95, 95%CI 1.29-2.95, p=0.007) and genotype Asp/Asp (OR=2.56, 95%CI 0.98-6.72, p=0.04) were associated with the risk of metabolic syndrome in Slavic population. Patients with metabolic syndrome carrying genotype Asp/Asp had higher serum endothelin-1 level in comparison with Glu/Asp and Glu/Glu carriers.

The content of serum albumin was evaluated in the vitreous body, retina, and lens of human fetuses of 14, 16, 17, 18 and 24 weeks of gestation. Albumin was detected in these tissues. PCR analysis revealed no albumin mRNA in the retina or in the lens, while in fetal liver (control) mRNA for this protein was expressed. These findings suggest that serum albumin is not synthesized by cells of retina and lens, but is captured by them. The presence of serum albumin in human eye tissues suggests its involvement in the metabolism, maintenance of tissue volume, and antioxidant reactions.

Application of anxiolytic drug Selank to hippocampal slices increased the amplitude and discharge rate of spontaneous inhibitory postsynaptic currents in rat hippocampal pyramidal CA1 neurons. In some neurons, Selank-induced up-regulation of spontaneous inhibitory postsynaptic currents was preceded by a transient decrease in this activity. In the examined concentration range (1-8 μM), Selank demonstrated no significant dose-dependence.

Morphological changes in the thymus of female Wistar rats with experimental mammary gland carcinomas were studied. After adjuvant therapy, the area of the cortical matter and density of parenchymal cells in the thymus decreased, while areas of the medulla, connective tissue, and content of immunoblasts and macrophages increased. In the thymuses of rats receiving exogenous DNA, morphological signs of activation of the lymphoid and epithelial components were found: areas of the cortex and medulla, glandular and connective tissue corresponded to the values in intact animals, the counts of lymphocytes in the central part of the cortical matter and of macrophages in all zones of the thymus increased, and lymphocyte migration from the thymus increased (in comparison with the chemotherapy group).

The study established enhanced expression of vascular endothelial growth factor (VEGF) in the subpopulation of osteoblasts located in the regeneration region of femoral bone fracture near the titanium implants with bioactive calcium phosphate and hydroxyapatite coatings and suppressed activity of transforming growth factor-β2 (TGF-β2) in chondroblasts during the two weeks after surgery. In the delayed posttraumatic period, the distribution of TGF-β2 inversely related to its maximal activity. The data revealed the up-regulating effect of bioresorbable coatings on expression of VEGF and TGF-β2 and their implication in the control over various stages of reparative osteogenesis.

Histomorphometric and immunohistochemical analyses showed season-dependent changes in the morphofunctional parameters of the structural components of the thyroid gland in males of indigenous (Yakuts, Evens, and Evenkis) and non-indigenous (Russian and Ukrainians) populations of the Republic of Sakha (Yakutia) in different seasons. External and internal diameters of follicles and area of the colloid in the thyroid gland was higher in non-indigenous than in non-indigenous individuals both in summer and in winter. The height of thyroid epithelium, areas of thyrocytes and their nuclei, and nucleocytoplasmic index of the thyroid gland were lower in men from non-indigenous population in summer, and higher in winter than in non-indigenous inhabitants. Transition of a part of follicular apparatus of the thyroid gland to enhanced activity during winter was less pronounced in indigenous males in comparison with non-indigenous subjects.

Exposure to endocrine disruptors is considered as a risk factor thyroid gland diseases. We analyzed cytophysiological changes in rat thyroid follicular epithelium after long-term exposure to low doses of the most widespread disruptor DDT. Analysis of thyroid hormone production and light and electron microscopy of thyroid gland samples revealed cytophysiological changes in thyroid epithelium related to impaired transport through the apical membrane, suppressed Golgi complex activity, and impaired thyrotrophic hormone regulation of the secretory functions of thyroid cells, which led to compensatory transition from merocrine to microapocrine secret release.

We studied some structural and functional parameters of erythrocyte membranes in mice at the late presymptomatic and early symptomatic stages of experimental Parkinson’s disease induced by administration of MPTP (hemolysis, microviscosity of different regions of the lipid bilayer, LPO intensity, activity of antioxidant enzymes, and kinetic properties of acetylcholinesterase). At the presymptomatic stage, significant deviations of the studied parameters from the normal were observed; they were similar in direction and magnitude to those in humans with Parkinson’s disease. At the early symptomatic stage, most parameters tended to normal. Microviscosity of bulk lipids increased at the presymptomatic stage and decreased after appearance of clinical symptoms. This dynamics probably reflects activation of compensatory mechanisms aimed at inhibition of oxidative stress triggered by the development of the pathological process.

Brain EEG-fMRI activity was studied in subjects, who had successfully completed the EEG alpha stimulating training course (20 sessions): for 14 healthy men (20-35 years) three records were obtained in the feedback loop (biofeedback with EEG alpha rhythm with sound reinforcement): in the beginning, middle and at the end of the course. During alpha training, increased functional connectivity was revealed between precuneus network and anterior salience network, left executive control network, default mode network, primary visual network; anterior salience network and executive control network, visual-spatial network. The most prominent changes were found for precuneus network and anterior salience network, which could be due to their key role in the biofeedback phenomenon. Significant changes in functional connectivity were recorded for anterior salience network and precuneus network (synchronicity increased from the first to the third trial) and right and left executive control networks (weakening from the first to the second session.

A putative opioid agonist RU-1205 was ineffective within in vitro model of electrically induced contractions of rat ileum assessing the μ- and δ-opioid receptor pathways, while morphine inhibited these contractions in a dose-dependent and naloxone-reversible manners with EC₅₀=2.6×10^—7 M. In vivo experiments revealed no significant effects of RU-1205 on respiration and gastrointestinal tract contractile activity. In contrast, butorphanol decreased respiration rate by 25% (25-100 mg/kg) and slowed down the transit of labeled particles along the small intestine by 77.1% (1 mg/kg) and by 45.5% (10 mg/kg). Morphine-induced inhibition of peristalsis was dose-dependent with maximum effect (by 68.6%) observed in the dose of 10 mg/kg. It was concluded that the effects of RU-1205 are not related to activation μ- and δ-opioid receptors known to mediate the effects of non-selective opioid agonist morphine and agonist-antagonist butorphanol.

Early fibrosis of the visceral organs is one of the main complications of infection caused by influenza A virus. Structural manifestations and molecular regulators of the epithelialmesenchymal transformation as a possible mechanism of fibrosis progression were studied in mice infected with influenza A/H1N1 A/Tomsk/13/2010 virus. We found early fibrosis of the lungs against the background of minor changes in fibroblast count. However, enhanced expression of TGF-β and SMAD-2 by macrophages and alveolocytes attested to possible development of epithelial-mesenchymal transformation and its contribution to activation of fibrogenesis process in the lungs.

We studied the relationship between polymorphisms rs1800629 (-308G>A), rs28362491 (-94ins>del), and rs3834129 (-652ins>del) in the promoter regions of TNFA, NFKB1, and CASP8 genes, respectively, encoding TNF-α, nuclear transcription factor κB1 (NF-κB1), and caspase 8 (CASP8), and the risk and stages of chronic lymphocytic leukemia in ethnic Russians, residents of the Vyatka region of Russia. Allele -308A, genotype -308AA, and -308A genotypes (-308AA/-308AG) were associated with the risk of this pathology (OR=1.64, 95%CI 1.14-2.37, p=0.007; OR=4.48, 95%CI 1.20-16.80, p=0.02, and OR=1.57, 95%CI 1.05-2.36, p=0.03). In addition, NFKB1 allele -94del and genotype -94del/del were associated with advanced stages of the disease at the time of diagnosis (OR=0.66, 95%CI 0.46-0.97, p=0.03 and OR=0.43, 95%CI 0.20-0.92, p=0.03). These data suggest that -308G>A and -94ins>del polymorphisms of genes TNFA and NFKB1, respectively, can be involved in the pathogenesis of chronic lymphocytic leukemia.

First-fourth order pial branches of the median cerebral artery were studied by biomicroscopy in male Wistar rats aged 1 and 12 months. Irrespective of age, CO-mediated mechanisms are involved in the regulation of the basal tone of pial vessels of various diameters (more so of arteries with well-developed muscular tunic). Injection of hemin confirmed that endogenous production of CO maintained vasodilatation and this effect was most pronounced in large pial branches of young animals, while zinc protoporphyrin IX blocked this effect in all cases. On the other hand, zinc IX protoporphyrin did not modify NO-mediated reaction caused by injection of L-arginine, while hemin compensated (though not completely) vasoconstriction induced by NO synthase blocker L-NAME. In contrast to NO, the effect of CO on blood vessels was not so rapid and potent, but more lasting. Other targets for CO were arteries with well-developed muscular tunic, while targets for NO were small vessels. The vasomotor effects of both gas transmitters were more pronounced in young animals.

For evaluation of the efficiency of bone substitute, nanostructurized Gamalant-paste-FORTEPlus was placed into a mandibular defect in rats. Bone tissue reparation was evaluated after 30 days by histological methods under a microscope. Use of bone substitute in experimental mandibular defect ensured more complete and rapid restructuring of the bone tissue in comparison with the control (natural healing).

We examined HCV+ and HCV- hemophilia A patients with knee arthropathy and hematocrit above 38.5%. The mean density of erythrocytes was studied by the phthalate method, intraoperative blood loss was assessed gravimetrically. The volume of blood loss in HCV+ patients with manifest adhesive process and chronic synovitis varied from 300 to 1900 ml, in patients with moderate adhesive process from 400 to 1500 ml. The volume of blood loss in HCV- patients was 300-800 ml. A positive correlation between the blood loss volume and mean density of erythrocytes was detected. Blood loss >1000 ml during total knee arthroplasty can be expected in patients with hemophilia A with HCV and high mean density of erythrocytes. Blood loss >1000 ml is unlikely in HCV- and HCV+ patients with the mean density of erythrocytes not surpassing the normal values.

The cholinergic, GABAergic, and catecholaminergic neurons derived from mouse embryonic stem cells in a culture medium supplemented with recombinant NGF were phenotyped and scored. NGF stimulated generation of neurons, but not neuronal progenitors from embryonic stem cells and affected the proportion of specific types of neurons in cultures of differentiating embryonic stem cells. These findings open vista to employ NGF for generation of specific neuron types from embryonic stem cells for fundamental and toxicological studies.

Morphological analysis of the subcutaneous fat was performed in rats after subcutaneous implantation of basic dental plastic materials with different hydrophobic and hydrophilic properties. It was shown that subcutaneous implantation of dental plastics with mostly hydrophobic surface and low biocompatibility induced destructive and inflammatory processes of various intensities, sometimes with allergic component; morphological signs of processes persisted for 6 weeks. Modification of basic plastics using glow-discharge plasma and enhancement of their hydrophilicity and biocompatibility significantly reduced the intensity of destructive and inflammatory processes and ensured more rapid (in 2 weeks) repair of the destroyed tissues with the formation of fibrous capsule around the implant.

We modified the protocol of obtaining of biological scaffolds of rat lungs based on dynamic recording of specific resistivity of working detergent solution (conductometry) during perfusion decellularization. Termination of sodium deoxycholate exposure after attaining ionic equilibrium plateau did not impair the quality of decellularization and preserved structural matrix components, which was confirmed by morphological analysis and quantitative assay of residual DNA.