[Role of plasmalemma in the process of aging, elimination and reproduction of erythrocytes: plasmalemmal microvesicles as stimulators of erythropoiesis]. / Rol' plazmalemmy v protsessakh stareniia, eliminatsii i vosproizvodstva eritrotsitov: mikrovezikuly plazmalemmy kak stimuliatory eritropoeza.

This study summarizes the experimental findings suggesting that plasmalemmal microvesicles formed from red blood cell aging are stimulators of erythropoiesis. The supposed sequence of events consists of microvesicular absorption by the settled macrophages of the liver and spleen, a message of information from circulatory monocytes (and lymphocytes) to the central macrophage of erythropoietic islands and regulation of late erythropoiesis. This is an autoerythronic regulation because it corrects red blood cell reproduction in relation to the rate of cell aging and thus differs from the classical humoral type which regulates erythrocytic reproduction according to visceral oxygen supply.

[Stimulation of erythropoiesis in hemorrhage during pregnancy using microvesicles from erythrocyte plasmolemma]. / Stimuliatsiia éritropoéza pri krovopotere na fone beremennosti s pomoshch'iu mikrovezikul iz plazmolemmy éritrotsitov.

Autologous microvesicles of erythrocyte plasmalemma were obtained by means of ultrasound treatment of erythrocyte suspension. These microvesicles were intravenously (i.v.) injected to pregnant rabbits with artificial bleeding at the 21st day of gestation. Three i.v. injections of microvesicles with 1-3 day interval at the amount equal to 1% of the weight of the circulating erythrocyte plasmalemma increased almost to the control level the number of erythrocytes and hemoglobulin by the 8th day after the bleeding while these indices were much lower in untreated animals.

Functional characteristics of the mature and developing brain following neuroimmunization: analysis of short-term plasticity in the rat hippocampus.

The influence of neuroimmunization by the total antigens of the cytosol fraction of hippocampal tissue or neocortical tissue on the indices of short-term plasticity in adult and developing (3 to 4 week old) Wistar rats has been investigated. Short-term plasticity was evaluated on the basis of changes in the slow-wave component of the focal potentials (FP) of the CA3 field of the hippocampus upon stimulation of the region of the dentate gyrus. The FP were recorded under nembutal anesthesia. In the groups of the hippocampus of adult and developing immunized rats, the greatest changes in short-term plasticity in the form of extreme intensification of the expressivity of the properties of paired facilitation and frequency potentiation were confined to the pyramidal layer. In the neocortex groups, the changes, as a rule, were less marked, and had the opposite sign; the main differences were found in the recording of the FP in the zone of the apical dendrites of the pyramidal neurons. It was noted that the focal activity of the young immunized animals is characterized by greater maturity as compared with the age norm. A conclusion is drawn regarding the different primary localization of the targets of the neuroimmune effect when antigens of different brain structures are used, namely hippocampus versus neocortex, and regarding the dependence of the physiological effect of neuroimmunization on the degree of maturity of the target structure.

[Functional characteristics of the mature and developing brain following neuroimmunization: an analysis of the short-term plasticity of the rat hypothalamus]. / Funktsional'nye kharakteristiki zrelogo i razvivaiushchegosia mozga posle neiroimmunizatsii: analiz kratvovremennoi plastichnosti v gippokampe krys.

In experiments on mature and developing (3-4 weeks old) rats the influence was shown of neuroimmunization with summate antigens of hippocampal or neocortical tissue cytosolic fraction on short-term plasticity of hippocampal CA3 field potentials under dentate gyrus zone stimulation. An increase of paired facilitation and frequency potentiation was revealed in pyramidal layer responses of hippocampal tissue immunized animals. In case of immunization with neocortical antigens the changes were less expressed, had mainly the opposite direction and took place in the apical dendrites zone. In young animals besides antigen spectrum depending effects of neuroimmunization an earlier manifestation (in comparison with age norm) of some focal activity definitive properties was described. The suggestions are made about different localization of hippocampal or neocortical tissue immunization "targets" with possible preferential damage of intrahippocampal systems when using this structure antigens, and also about dependence of physiological consequences on the extent of target structure ontogenetic maturity.

[Changes in the permeability of vesicules from isolated apical membranes of rabbit small intestine epitheliocytes to K+, Na+, H+ during Ca-activated lipolysis]. / Izmeneniia pronitsaemosti vezikul iz izolirovannykh apikal'nykh membran épiteliotsitov tonkoi kishki krolika dlia K+, Na+, H+ pri Ca-aktiviruemom lipolize.

pH-dependence of Ca2+-activated hydrolysis of self phospholipids was studied in vesicles from the apical epitheliocyte membranes of the rabbit small intestine. It was shown that lipolysis had pH optimum at 7.0 and involved phospholipases A2 and A1 (or lysophospholipases). Marked changes in vesicle permeability for cations are observed during 40-50% phospholipid hydrolysis.

[Establishment of the afferent function of the striatum in the rabbit during early ontogenesis]. / Stanovlenie afferentnoi funktsii striatuma u krolikov v rannem ontogeneze.

The study is dedicated to electrophysiological analysis of development of the caudate nucleus afferent function in rabbits in early postnatal ontogenesis. By amplitude-temporal parameters of the evoked potentials (EPs) of the caudate nucleus, recorded in response to stimulation of afferent inputs from the cortical regions (motor and limbic) and substantia nigra, similar dynamics of these afferent pathways functional maturation is revealed from the beginning of functioning (in the age of 3-5 days) to the definitive level (by the 30th day of life). The most significant changes of the amplitude-temporal parameters of the evoked potential, particularly of latencies are observed during the 3d week of postnatal life. On the basis of the obtained data, the conclusion is made on the formation of a common system of striatum sensory integration in the 3d-4th week of rabbits life. This age period is considered as critical.

[Changes in the indices of lipid peroxidation in liver mitochondria of white rats during simulation of in vitro anoxic damage]. / Izmeneniia nekotorykh pokazatelei perekisnogo okisleniia lipidov mitokhonrii pecheni belykh krys pri modelirovanii ikh anoksicheskogo povrezhdeniia in vitro.

Lipid peroxidation was studied in the course of the development of anoxic injury to the mitochondria in vitro. Hydrolysis of mitochondial phospholipids was accompanied by an increase in antioxidant activity (AOA) of the organelles. At the same time the ability to transoxidation in liposomes formed from lipids extracted from the injured mitochondria was discovered to be increased. It is assumed that AOA of the mitochondria rises at the expense of antioxidants not extractable with a mixture of chloroform and methanol.

[Use of a colorimetric method employing rhodamine 6G for determining the free fatty acid content in biological membranes]. / Primenenie kolorimetricheskogo metoda s ispol'zovaniem rodamina 6Zh dlia opredeleniia soderzhaniia svobodnykh zhirnykh kislot v biologicheskikh membranakh.

An improved modification of the Anderson-Chakrabarty method for demonstration of free fatty acids in the membranes of enterocytes, erythrocytes and mitochondrial fractions is described. The method includes the use of rhodamine 6G as a stain.

[Functional connections between the limbic cortex and caudate nucleus in young animals]. / O funktsional'noi sviazi limbicheskoi kory i khvostatogo iadra u molodykh zhivotnykh.

In anesthetized rabbits of 2-3-month age, stimulation of 24, 23, 29 limbic fields evoked potentials of the maximal amplitude in dorsomedial parts of the caudate nucleus ahead of the commissura anterior junction. Functional connections of anterior limbic cortex with the caudate nucleus are more obvious than these of posterior limbic cortical areas (23, 29). They occupied two medial thirds of the caudate nucleus. Short latency of the evoked potentials (4-5 msec) suggests that direct limbic cortex afferent connections of the caudate nucleus are well developed in 2-3-month old rabbits.

[Hypothalamo-hippocampal mechanisms in the organization of orienting-explorational behavior in the exaltation period of ontogeny]. / Gipotalamo-gippokampal'nye mekhanizmy v organizatsii orientrovochno-issledovatel'skogo povedeniia v ékzal'tatsionnom periode ontogeneza.

Gross and unit hippocampal responses to electrical stimulation of the dorsal hypothalamus nuclei, eliciting well defined motor acts related to orientation and investigation of the situation, were studied in rabbits, four to six weeks old, during the exaltation period of their ontogenesis. Shifts of the theta-rhythm frequency revealed in the hippocampus against the background of developing motor components of behaviour, as well as reactions of single units, were characterised by a prolonged stimulus after-effect. The tonic activation response was the predominating type of cellular reaction. A disbalance of phasic activating and inhibiting reactions was observed, the latter tending to prevail. A conclusion was drawn that the recorded reorganizations of hippocampal activity in the rabbits of the studied age reflect a lack of lability of the inhibitory-excitatory processes in the hypothalamo-hippocampal link of the functional system of the orienting reflex.

[Functional and morphologic characteristics of limbic cortex maturation during early ontogenesis]. / Funktsional'nye i morfologicheskie kharakteristiki sozrevaniia limbicheskoi kory v rannem ontogeneze.

Development of the limbic cortical area in postnatal ontogenesis of the rabbit comprises three periods judging by the parameters of impulse activity of neurones and cytoarchitectonic differentiation. The period of stratification and beginning of cellular differentiation functionally corresponds to the manifestation of simple forms of spike activity (single, group) with long inactivation periods (the first week of life). The period of intensive cytoarchitectonic differentiation with separation of the agranular type of the anterior limbic area structure correlates with a more complex neuronal impulse activity (burst discharges), augmenting spectrum of dominating spike frequencies, predominance of phasic activation and specific responses together with a high total neuronal responsiveness to sensory (acoustic) stimuli (the second to third week of life). The period of complete cytoarchitectonic maturation corresponds to the stabilization of functional properties of neurones (the fourth to sixth week of life). The revealed ontogenetic dynamics of morpho-functional reorganizations in the limbic cortex point to its involvement at an early stage of postnatal life in the mechanisms of sensory analysis and of the formation of adequate adaptive reactions.

[Functional characteristics of the hippocampus after switching off visual afferentation in early ontogenesis]. / Funktsional'nye kharakteristiki gippokampa pri vykliuchenii zritel'noi afferentatsii v rannem ontogeneze.

EEG reactions to afferent stimuli and the driving responses (DR) to photic flickering with 1-15 sec frequency were studied in different brain structures of rabbits lacking visual experience (from the 8th to the 23rd and from the 57th to the 90th day of life). The orienting reaction in the first few days of the light regime is characterized by enhanced motor and respiratory components and is not extinguished for a long time when the stimulus is repeated. It is attended with theta-rhythm in the hippocampus EEG and desynchronized activity in the neocortical areas. DR is characterized by spatial-temporal dissociation; its development is markedly retarded in the cortical projection zone of the visual system, and of the archicortex structures, in the dentate fascia, as compared with the hippocampus proper, the midbrain reticular formation and the auditory cortex. The DR index equals the level of that of the control animals after nine to twelve days of their life in the light. The results obtained attest that the observed differences in the changes of the functional characteristics of the hippocampus and other brain structures depend on the mode of the central organization of the reaction, whose correlate is the studied EEG-parameter.