[Functions of microglia in the healthy brain: focus on neuroplasticity].

Microglia is in the center of modern research because it is involved in neuroinflammation processes, which is considered as an important part of pathogenesis of many brain pathologies. On the contrary, normal physiological functions of microglia are less studied. Here we review modern data on functioning of microglia in the healthy brain.

[Molecular and cellular mechanisms of depression. Role of glucocorticoids, cytokines, neurotransmitters, and trophic factors in genesis of depressive disorders].

Here we review modern data on appearance and maintenance of depression at different levels of the body. We discuss a role of impairments of emotional and motivation mechanisms of adaptive behavior in genesis of depression. We demonstate an interaction of stress response and neuroinflammatory processes in pathogenesis of depression and analyze the effects of these molecular cascades on neurotrophic support of the central mechanisms of memory and neurogenesis.

[The effect of childhood stress on the development of mental disorders in adults].

There is evidence that not only severe stressful events, but also common low-threat events, in particular chronic ones, may cause or provoke some mental disorders. The literature data on the degree of pathogenicity of stress factors are insufficient. Authors attempted to summarize the established facts in the following aspects: current conceptions on the physiology and pathology of stress in the frames of the problem of psychosomatic disorders, deprivation in childhood, neurobiological consequences of childhood stress, psychiatric consequences of stress in childhood.

[Biomarkers in multiple sclerosis (a review and experimental data)].

Identification of biomarkers in multiple sclerosis is a very complex problem, and intensive work is being made in this field for the last decades. The importance of establishing biomarkers of multiple sclerosis is related to the high disease heterogeneity and lack of characteristic symptoms that leads to diagnostic, prognostic challenges and difficulties in making decisions about therapy. In this paper, we review the most important biomarkers and discuss their diagnostic and prognostic value.

[Role of NO/cGMP signaling cascade in the development of opium dependency].

This study was aimed at evaluating the role of nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) cascade in mechanisms of morphine dependency formation. Morphine was introduced by intraperitoneal (i.p.

[Effects of stress factors on adult hippocampus: molecular, cellular mechanisms and dorso-ventral gradient].

Adult hippocampus is one of the brain structures selectively vulnerable to stress factors. In the hippocampus, stress-induced neuroinflammation, neurodegeneration, epileptic activity and disturbances of neurogenesis take place. Stress of different modality specifically affects hippocampal structural and functional plasticity, the primary target of the stress hormones are corticosteroid receptors (glucocorticoid and mineralocorticoid receptors).

[Involvement of Wnt signaling in hippocampal plasticity].

Wnt signaling is a signal transduction pathway involving peptides of Wnt family as key molecules. In this review, the data on the role of canonical and non-canonical Wnt pathway in hippocampal structural and synaptic plasticity have been analyzed. Wnt-mediated signal transduction is involved in normal functional plasticity, and the disturbances in Wnt-mediated mechanisms form a basis for the development of cerebral pathologies.

[Neurodegenerative changes in rat hippocampal areas during the pentylenetetrazole kindling development].

The development of pentylenetetrazole-induced kindling is accompanied by neurodegeneration and neuronal loss in different areas of the hippocampus. However, the data on neurodegeneration development in the dentate gyrus remain controversial. In our study that was performed on 20 Wistar male rats, it was found that the process of neuronal loss was expressed unequally along the dentate gyrus.

[Assessment of caspase-3 activity in rabbit myocardial tissue during experimental hemodynamic overload of the left ventricle of the heart].

It's well known that chronic overload of the cardiac left ventricle is accompanied by an increase in the cardiomyocyte apoptosis rate. However direction and extent of programmed cell death changes under an acute overload of the left ventricle still requires detailed investigation. Caspase-3 activity has been investigated in myocardium of rabbits on the 1, 3 and 5 days after modeling of left ventricle hemodynamic overload caused by surgical narrrowing of the ascending aorta.

[Akatinol memantine in patients with vascular cognitive disorders].

Treatment of cognitive disorders developed in cerebrovascular pathology is an actual medical problem. Of great importance is the timed diagnosis of these changes in the earlier phases of the development of cognitive deficit as well as adequate therapy that can delay and prevent the development of such complication as dementia. Pathogenetic mechanisms of cognitive disorders are associated with brain vascular and neurodegenerative changes that determine using drugs with vasoactive, metabolic and/or neuromediator effects.

[Evaluation of antiepileptic effects of cortexin in a model of convulsions].

We studied antiepileptic effects of cortexin administered in doses 0,015, 0,15 and 1,0 mg/kg intraperitoneally in solution or intranasally in the complex with nanoparticles in a model of acute and chronic convulsions in rats induced by pentylenetetrazole. In the model of epileptic status, the long-term preliminary administration of cortexin had no effect on convulsions while in the model of chronic convulsions (temporal epilepsy), cortexin had a marked dose-dependent antiepileptic effect. The influence of cortexin on neuroplasticity and its clinical potential are discussed.

[Remote control of the goal-directed behavior of freely moving rats by telestimulation of the rewarding brain structures].

The procedures are described that make it possible to train laboratory rats for remote control of their goal-directed behavior in open environments by telestimulation of rewarding brain structures. Rats were implanted electrodes in the lateral hypothalamus and lateral preoptic area. A week after surgery, rats were placed in an operant chamber and given electrical stimulation of increasing/decreasing intensity to each location to determine the most suitable site/hemisphere for reward delivery as well as the optimal stimulation parameters and the thresholds of behavioral reactions elicited.

[Reduction of the number of mutant copies of mitochondrial DNA in tissues of irradiated mice in the postradiation period].

Changes in the number of mutant copies of mitochondrial DNA (mtDNA) were studied in the brain and spleen tissues of mice after their X-irradiation at a dose of 5 Gy. For this purpose, heteroduplexes obtained via hybridization of the products of PCR amplification of mtDNA (ND3 gene and two D-loop regions) from irradiated and control mice were digested with the CelI nuclease capable of specific mismatch cleavage. Heteroduplexes obtained via hybridization of the products of PCR amplification of mtDNA from irradiated and control mice were digested by the CelI nuclease to a greater degree than heteroduplexes of the PCR products of mtDNA of mice from the control group.

[Active avoidance learning in rats and morphological changes in the hippocampus after pentylenetetrazole kindling].

The relationship between parameters of active avoidance conditioning and morphological changes in the hippocampus was investigated using pentylenetetrazole kindling animal model of epilepsy. Pentylenetetrazole kindling impaired learning of escape reaction and increased the number of intertrial crossings in a shuttle box during active avoidance conditioning. Kindling decreased the number of neurons in the hippocampal CA1 and CA3 fields and in the dentate gyrus and increased the number of abnormally changed neurons, which displayed cell shrinkage and chromatophilic staining.

[The comparative determination mutations in mtDNA of irradiated mice using mismatch-specific endonuclease and TTGE-technique].

We defined the mutations in mtDNA of X-irradiated mice brair using mismatch-specific endonuclease (CEL I-nuclease method) and by temporal temperature gradient gel electrophoresis (TTGE-technique). The comparison of the received by both methods, allows to conclude, that CEL I-nuclease method gives more qualitative results, than TTGE-technique. Moreover, CEL I-nuclease method is more sensitive, in contrast with TTGE-technique.

[The use of temporal temperature gradient gel electrophoresis to reveal mutations in peripheral blood mitochondrial DNA].

The mutations in mitochondrial DNA (mtDNA) arise at a higher frequency than in nuclear DNA, and their appearance in peripheral blood can be considered as a sensitive marker to estimate the level of genotoxic load. For revealing the presence of mutations in mtDNA of peripheral blood, we used the method of temporal temperature gradient gel electrophoresis (TTGE). The samples of whole blood DNA from four donor groups were used.

[Developmental caspase-3 activation in the rat hippocampus is involved in the maturation of instrumental behavior].

Previously the developmental switch to caspase-3 activation in the rat hippocampus has been shown during the third week of life. The goal of this study was to explore effects of caspase-3 inhibition during this period on learning in a two-way avoidance paradigm. On postnatal day 18, the pups were intracerebroventricularly administered with caspase-3 inhibitor Z-DEVD-FMK.

[Caspase-3 activity in the rat hippocampal slices reflects changes in synaptic plasticity].

Considering the involvement of caspase-3 in neuronal plasticity, we studied caspase-3 activity in the rat hippocampal slices, and electrophysiological characteristics of extracellular responses to paired-pulse stimulation of Schaffer's collaterals in the CA1 subfield of hippocampus. Caspase-3 activity was measured after electrophysiological recording in each slice separately. Maximal caspase-3 activity was observed in the slices with low responsiveness to single afferent stimulation indicative of decreased efficacy of interneuronal interaction.

[Epileptic seizures in patients with stroke: risk factors and mechanisms of their development].

The current state of the problem of epileptic seizures developed after ischemic and hemorrhagic stroke is presented. Etiology, pathogenesis risk factors of epileptic seizures and their impact on the course and severity of stroke are reviewed. It has been shown that "early" and "late" epileptic seizures have different mechanisms of development.

[Anxiety level during morphine abstinence correlates with the status of nitrergic system in the rat hippocampus].

Opiate addiction is accompanied by long-term structural and functional changes in brain regions persisting during abstinence, this status being an experimental model of the aberrant neuroplasticity. Nitric oxide is known to be involved in mechanisms of psychopathological events during opiate abstinence. In this study, indices of a nitregic system (nitric synthase activity--NOS, nitrites and nitrates concentration--NOx-) were measured in the rat brain region during morphine abstinence.

[Kindling during early postnatal development: the effects on the maturation of the hippocampal electrophysiological characteristics].

The effect of repeated pentylentetrazole (PTZ) administration on the postnatal development of hippocampal electrophysiological indices has been studied. Contrary to adult rats, repeated PTZ injections did not intensify convulsive activity in rat pups (from postnatal day 14). We did not observe any between-group differences in population spike amplitudes and paired pulse facilitation (PPF) ratio at 70 ms interpulse interval during early period of postnatal development, PPF suppression at short interlulse interval (15 ms) only was significantly less in PTZ group as compared with saline-injected controls, but the effect of saline injections has developed in the same directio However PTZ resulted in the modification of developmental profile.

[Nitric oxide synthase activity and nitrates/nitrites level in brain regions during the spontaneous morphine withdrawal in rats].

Nitric oxide synthase (NOS) activity and nitrate/nitrites (NO(x)-) concentrations were measured in brain regions of rats during the spontaneous morphine withdrawal. Male Wistar rats were injected intraperotoneally with morphine hydrochloride at increasing doses (10-100 mg/kg) during 6 days twice a day. Thirty six hours after the last injection the severity of the spontaneous morphine withdrawal syndrome was determined by specific autonomic and locomotor indices.

[Changes in copy number and deletion development of mitochondrial DNA in blood cells from breast cancer patients during radiochemotherapy].

Changes in mitochondrial DNA (mtDNA) copy number were compared versus the nuclear beta-globulin gene (internal standard), as well as occurrence of large mtDNA deletions in peripheral blood samples from 21 breast cancer patients following chemoradiotherapy. The study used polymerase chain reaction. Distinct variations were identified both in mtDNA copy number versus nuclear DNA and large mtDNA deletions occurrence in blood cells in response to genotoxic influence of chemoradiotherapy.

[Proteins associated with mitochondrial DNA protect it against the action of X-rays and hydrogen peroxide].

It has been suggested in a number of investigations that the high vulnerability of mitochondrial DNA to reactive oxygen species and other damaging agents is due to the absence in mitochondria of histones complexed with DNA. In the present study it was shown that DNA-binding proteins of mitochondrial nucleoids were able to shield mitochondrial DNA from X-ray radiation and hydrogen peroxide, as nuclear histones did. Mitochondria, mitochondrial nucleoid proteins, and histones were isolated from mouse liver cells.

[Effects of intracerebroventricular administration of a caspase-3 inhibitor Z-DEVD-FMK on behavior of rats].

Rats received intracerebroventricular injections of z-DEVD-FMK (caspase-3 inhibitor) or z-FA-FMK (control peptide) in a dose of 3 nmol. Administration of z-DEVD-FMK significantly decreased the number of avoidance reactions in some blocks of trials in active avoidance (shuttle box) learning. However, only slight effect of the caspase inhibitor across the session was found.