[The possible role of nitrogen dioxide produced in the field of bifurcation of vessels, in the processes of their damage in hemorrhagic strokes, and the formation of atherosclerotic plaques].

According to modern views the formation of atherosclerotic plaques is associated with accumulation of cholesterol in the vascular wall. This is due to an imbalance between the intake of cholesterol in the intima of vessels, together with the low-density lipoproteins (LDL) and its output with high-density lipoprotein (HDL). Change of LDL (glycosylation, lipid peroxidation, hydrolysis of phospholipids) and the effective release of cholesterol from the endothelium of the vascular wall are the factors that cause an imbalance in cholesterol metabolism. In this paper we propose a new concept of the mechanism of initial formation of atherosclerotic plaques, which can complement the existing concepts. According to this concept an important role in the early stages of atherosclerosis are highly reactive molecules of nitrogen dioxide (NO2), resulting from the violation of the cycles of nitric oxide and superoxide anion radical. Hypothesized that the mechanism of antiradical protection of cells and the organism as a whole, above all, laid out in most of the cyclic organization of metabolic processes that involve the formation of free radicals. Violation of this cyclic mechanism may be one of the causes of many diseases associated with hypoxia/ischemia and inflammation. The review considers the hypothesis of the possibility of participation of NO2 and OH-radicals formed in violation of the cycles of NO and superoxide, in the mechanisms of vascular damage with hemorrhagic stroke and in the formation of atherosclerotic plaques.

[Influence of carbon dioxide on the impregnation of the nervous tissue by silver].

It has been shown that 4% carbon dioxide (CO2) in the air above reaction mixture inhibits the initiation of the formation of silver nanoparticles from complexes with biogenic amines (noradrenaline and serotonin). At the same concentration of CO2 in the air above solution of AgNO3, which is used for staining nerve tissues by the method of Golgi, neurons are preferentially stained, whereas at a concentration of 0.06%, vessels and poor neurons are stained. It is suggested that the entry of free silver ions to neurons is due to the inhibition of sites of initiation of silver nanoparticles in vessels at high CO2 concentrations, while the lack of inhibition leads to silver precipitation in vessels at low CO2 concentrations. It can be assumed that, for stable silver impregnation, the concentration of CO2 must be controlled.

Morphofunctional interactions of peripheral nerve fibers of the iris with neurons developing in the anterior chamber of the eye in rats.

Electron microscopic studies were performed on intraocular transplants of embryonic septal and hippocampal tissue developing in the anterior chamber of the eye in rats for 3-4 months. The aim of the study was to seek ultrastructural identification of peripheral nerve fibers entering transplants from the iris, and to assess their ability to establish true synaptic contacts with transplanted CNS neurons. Bundles of myelinated and unmyelinated axons surrounded by Schwann cell cytoplasm were seen within the perivascular spaces of ingrowing blood vessels. Both types of peripheral fiber were also identified in the neuropil areas of transplants. At the ultrastructural level, unmyelinated axons were found to be free of glial Schwann cell sheaths and to form typical asymmetrical synapses with the dendrites and dendritic spines of transplant neurons. These results provide evidence of the high morphofunctional plasticity of both parts (central, peripheral) of the nervous system.

[Influence of cortical neurotrophic factors on the neurocytokine production system in acute hemorrhagic stroke].

The mechanism of therapeutic action of cortical neurotropic factors (CNTF) was studied in hemorrhagic stroke. In intracerebral hemorrhage, CNTFs were shown to elevate the level of nerve growth factor mRNA and at the same time, produce no effect on its level in intact animals. The neuroactivating action of CNTF in the acute phase of hemorrhagic stroke was achieved by intranasal administration due to the retrograde axon transport of CNTF molecules along the olfactory nerve fibers to the brain, by passing the blood-brain barrier. It was ascertained that the molecules of tritium-labeled CHTF accumulated in the central nervous system following 20 minutes and the level of label accumulation is proportionally increased after 120 minutes. The pattern of accumulation of the intranasally administered label in the olfactory tract and olfactory bulb proves CNTF transportation along these structures of the nervous system. Therefore, when intranasally administered, CNTFs are able to transport to the central nervous system along the olfactory tract and to enhance the expression of nerve growth factor mRNA in hemorrhagic stroke.

[Procedures for modeling of hemorrhagic stroke].

Hemorrhagic stroke (intracerebral hemorrhage) is a socially significant cerebrovascular disease. Despite high mortality and disability rates, hemorrhagic stroke has been experimentally studied to a lesser extent than ischemic stroke. The modeling of hemorrhagic stroke may be used to solve a number of fundamental and practical problems. The present review deals with the review of the currently available procedures for modeling hemorrhagic stroke.

[The role of latent virus infection of the central nervous system in acute hemorrhagic stroke].

The purpose of the investigation was to study whether latent virus infection may activate in the murine brain using a model of hemorrhagic stroke. Acute intracerebral hemorrhagic stroke was induced in the internal capsule in accordance with the original technology. For experimental reproduction of virus meningoencephalitis, albino mice were infected with a sublethal dose of herpes simplex virus. The investigation ascertained persistent virus activation, as shown by the polymerase chain reaction technique that detected herpes simplex virus type 1 in the blood and brain of the animals, as well as the development of a cerebral inflammatory lesion associated with acute hemorrhagic stroke. The findings suggest that encephalitis may develop in acute stroke due to herpes simplex virus reactivation from the latent state, which will improve monitoring and treatment quality in acute stroke.

[Nitric oxide (NO) and NO cycle in myocardium: molecular, biochemical and physiological aspects].

The article continues the series of our publications on the problem of nitric oxide (NO) and its cyclic conversion in mammals. This review is held to analysis of nitric oxide role in regulation of cardiovascular system and in alocation of NO-synthases in myocardium. Molecular, biochemical and cytophysiological aspects that linked, with spatial localization of NO-synthases and mechanisms of NO content regulation in myocardium are considered. The results of author's investigations along the cyclic convertion of NO and literature data about compartmentalization of NO-synthases in myocardium are included in this paper. The contradictory and dissimilar facts about regulatory and toxic role of nitric oxide in cardiovascular system are represented.

[Nitric oxide is involved in the protective effects of short-term adaptaion to hypoxia in the course of stress-induced disorders in Krushinsky-Molodkina rats].

A possible involvement of nitric oxide in the protective effect of short-term adaptation of Krushinsky-Molodkina rats to mild hypoxia simulating 5000 m above sea level was studied. Nitric oxide proved to have a considerable protective effect on stress-induced disorders in Krushinsky-Molodkina rats as demonstrated using NO-synthase inhibitors and NO monitoring by electron spin resonance under different experimental conditions.

[Conception of P.V. Simonov about and "altruists" and "egoists" to 80th anniversary of P.V. Simonov (20.04.1926-06.06.2002)].

Academician P.V. Simonov is known, first of all, as the founder of "Information theory of requirements and behaviour". He was the first, who declared that requirements are the main original source of behaviour's activity, evolution's regulator, the origin of creation and motive power of individual and collective actions of human beings and animals. In our paper we analyze some positions of Simonov's conception about "agoists" and "altruists", which has the grate practical value and are very actual today.

[Neurobiological studies of gamma-band bioelectrical activity in humans].

The modem literature data were observed, which dedicated to the study of neurobiological studies of gamma-rhythm mechanisms, providing the cognitive functions in hymans: state of readiness and attention, providing of sensory indentification, perception and memorizations, decision-making, management of psychomotor response, emotional and semantic processing of an information. It was shown that synchronous gamma-activity is at integrative activity, which in deteriorated in pathology of thinking. Literature data were analysed concerning ot the changes of gamma-activity (spontaneous, evoked, provoked by photostimulation etc.) in a number of neuropsychiatric disorders: epilepsy, schizophrenia, Alzheimer's disease, attention deficit hyperactivity disorder, stroke etc. as compared with norm. The data observed testify to high significance of gamma-activity in the brain functioning.

Modification of injection mapping of vascular-capillary bed in cerebral nervous tissue.

A simple original method of simultaneous staining of the cell elements on cerebral cortex and its vascular bed is developed. It is based on perfusion of polyvinyl acetate emulsion prepared on 2% paraformaldehyde solution with phosphate buffer at pH 7.4.

[Efficacy of cerebrolysin in cerebral hemorrhage model in rats].

The pharmacological efficacy of cerebrolysin (a brain-derived peptidergic drug) was studied in rats with a unilateral hemorrhagic stroke model. Cerebrolysin produces a neuroprotective effect, which is manifested by a decrease in the number of degenerated neurons in the vicinity of hematoma region in acute period and by a reduction of the neuronal loss in the early recovery phase. Besides, the administration of cerebrolysin improves the functional state as judged from the results of neurological and behavioral tests (open field, paw licking, and passive avoidance). A decrease in the hyperactivity in the open field test and the conservation of latent avoidance in the passive avoidance test demonstrate the drug influence on the maintenance of inhibitory processes deteriorated in stroke.

[Mechanisms of neurogenic dystrophies induced by activation and deprivation of the sympathetic nervous system].

Entry of abnormal nervous stimuli after sciatic nerve transection proved to affect the functioning of renal mineralocorticoid receptors as a result of inadequate neurotrophic support of this organ. Drug blockade of both neural and humoral transmission of the abnormal stimuli from the injured nerve to the kidney prevented development of trophic disorders as indicated by the status of the renal mineralocorticoid receptor system. At the same time, drug stimulation of the sympathetic nervous system further affected aldosterone reception by this organ. beta-Blocker propranolol was shown to exert an antidystrophic effect in the case of local injuries of the neural system and, thus, prevented the development of neurogenic dystrophies.

[Neurobiological approach to brain functional asymmetry in depression].

The modern literature data were observed, which dedicated to the study of neurobiological mechanisms of depressive states of different origin. The results of the investigations of structurally functional features of depression in healthy volunteers in experiments and in patients with the neurological diseases were viewed. The data cited confirm the modern concepts of R. Davidson concerning to the role of brain functional asymmetry in depression: i.e., the associations between depression and a decrease of the functional activation of the left prefrontal lobe, and also the involving of amygdale in the processes of the forming of negative emotions and depression. The literature data observed and findings of our investigations allow us to conclude that depressive states are characterized not only by the decrease of the functional activity of the left hemisphere, especially, its prefrontal area, but also reciprocal increase of the physiological activity of the prefrontal area of the right hemisphere combined with right-hemispheric functional insufficiency, especially, of its posterior (parieto-temporal) areas.

Intracortical synchronization of epileptic discharges at different stages of ultrastructural rearrangements in a completely neuronally isolated area of rat neocortex.

Cross-correlation functions were used to study the time delay (a measure of synchronization) in the appearance of epileptic discharges in distant areas of the cortex in the intact cortex and in neuronally isolated cortical strips in Wistar rats. Experiments were performed at different stages of axon sprouting 30 and 90 days after isolation of cortical areas and in intact cortex. Significant increases in the number of synapses in layer V of isolated cortical strips at 30 days correlated with significant decreases in the time delay, while decreases in the number of synapses at 90 days correlated with a significant increase in the time delay. This is evidence that newly formed synapses increase the extent of synchronization and thus affect epileptogenesis. The data obtained here suggest that large pyramidal cells in layer V of the rat neocortex form a neural network in pathological conditions, this supporting intracortical synchronization of epileptic discharges.