[The analysis of the possible pathways of carrying information and its integration in the projection systems, connecting the basal ganglia with the rostromedial tegmental nucleus dog's brain].

The structural foundation of processing of the information in the basal ganglia morphofunctional system was studied on the basis of the analysis of the projections between the separate parts of the rostral and thecaudal compartments of the rostromedial tegmental nucleus (RMTN) and the functionally different segments of the striatal and the pallidal structures, which were investigated by the method of the retrograde axonal transport. The elements of the topic, showing to opportunity of segregated carrying of the information between the limbic segments RMTN and the limbic striopallidal fields were revealed in the organization of the projections between the named structures in dog. But the convergence of the projection fibers, proceeding from the neurons of the functionally different parts of RMTN observed in the majority of striopallidal structures that testify about the opportunity of the integration of the functionally different information in them. The revealed labeled RMTN "reticular" neurons with sparsely branching dendrites and long axons, which are projected to the striopallidal structures, also testify about the integrative function of the investigated nucleus. The possible ways of carrying of the motor and the limbic information and its integration in the structures of the studied system and opportunity of the utilization of the received dates for making of the new models, which allow to understand better the mechanism of basal ganglia functioning in normal and pathological conditions are discussed.

[Organization of the projections of the substructures of deep mesencephalic nucleus to the striatum in the dog brain].

Method of retrograde axonal transport of horseradish peroxidase was used to study the organization of the projections of the individual substructures of the deep mesencephalic nucleus complex to the functionally diverse regions of striatal structures of the dog brain (n=20). It was shown that the projection fibers of the neurons of the nucleus profundus mesencephali were directed to the ventro-lateral segment of the nucleus caudatus and the ventral segment of the putamen. The dorsal segment of the putamen obtains the fibers from the neurons of the nucleus cuneiformis, while the lateral segment of the nucleus accumbens received them from the neurons of the nucleus subcuneiformis. The possible pathways for conduction of the functionally diverse information and its integration in the investigated projection systems are discussed.

[Interconnections of the pallidum, pedunculopontine nucleus, zona incerta, and deep mesencephalic nucleus--the structures of the basal ganglia morpho-functional system].

Method of anterograde and retrograde axonal transport of horseradish peroxidase was used to study the organization of projections of different substructures of zona incerta (ZI), pedunculopontine nucleus (PPN), deep mesencephalic nucleus (DMN) complex, and functionally distinct structures of the pallidum of dog brain (n=20). It was found that pallidum and nucleus entope-duncularis are connected by reciprocal projections with dorsal, ventral and caudal sectors of ZI, as well as with DMN, lateral segment of the pars dissipata, and the pars compacta of PPN. The rostral sector of ZI, cuneiform and subcuneiform nuclei of DMN complex, the medial region of PPN pars dissipata are connected by ipsilateral projections with the same pallidal nuclei. Among all the structures studied, the presence of reciprocal connections with the ventral pallidum was found only in the lateral segment of the pars dissipata and pars compacta of PPN. The possible pathways of transfer of functionally different information and its integration in the investigated projection systems, are discussed.

[The striopallidal projections of the zona incerta in the dog diencephalon].

The projections of individual sectors of the zona incerta (ZI) in dog diencephalon to the functionally different striatal segments were studied by the method of the antero- and retrograde axonal transport of horseradish peroxidase. The data on the interconnections of ZI with all striopallidal structures, obtained by the author before and in the present work were summarized. Among all the striatal nuclei, the the rostral, ventral and caudal ZI sectors contained the neurons that projected their fibers only to the dorsal segments of the putamen. Not a single striatal structure was found to form projections to ZI. ZI and the dorsal pallidal nuclei (globus pallidus, nucleus entopeduncularis) are reciprocally connected with almost all ZI sectors. The connections of the ventral pallidum with the ZI were not detected.

[NMDA-dependent increase of exracellular arginine level in the nucleus accumbens is mediated by NO-synthase activation].

In Sprague-Dawley rats, by means of in vivo microdialysis combined with HPLC analysis it was shown that intra-accumbal infusion of NMDA (10 microM, 100 microM, 1000 microM) dose-dependently increased the local dialysate level of arginine (an NO-synthase substrate). This increase was prevented by intraaccumbal infusion of 50 microM MK-801, an NMDA receptor antagonist, and it was significantly reduced by intra-accumbal infusion of 500 microM N-nitroarginine, an NO-synthase inhibitor. The data obtained indicate that extracellular level of arginine in the n. accumbens is regulated by NMDA receptors which act partially via NO-synthase activation.

[The analysis of the possible pathways of carrying information and its integration in the basal ganglia system on the basis of their interconnections with the zona incerta].

Possible ways of carrying functionally diverse information and its integration in the studied projection systems were analysed on the basis of investigation into peculiarities of the organization of projections between the zona incerta (ZI) of diencephalon and basal ganglia. In organization of the projections between these structures in dog, elements of topic were revealed showing to opportunity of segregate carrying of functionally various information in basal ganglia system. But the convergent carrying is the one most typical for these projection systems, that testifies to opportunity of integration of functionally different information both on the level of ZI and all basal ganglia structures studied in the present work.

[The connections of the zona incerta of the dog diencephalon with the substantia nigra, the ventral tegmental area and the pedunculopontine tegmental nucleus].

This study used the technique based on horse-radish peroxidase retrograde and anterograde transport to examine the organization of the connections of different sectors of the zona incerta (ZI) of the diencephalon with the substructures of the substantia nigra, the ventral tegmental area and the pedunculopontine tegmental nucleus of dog mesencephalon. It was found that these structures were interconnected with each other. In the organization of the projections studied, the elements were detected that suggested the possibility of the segregated conduction of the functionally various information via the established pathways. Alongside with this, the convergence of the projection fibres of the neurons of the mesencephalic nuclei substructures to ZI, described in all its sectors, together with the projections of all the ZI sectors to these neurons, indicates the possibility of the integration of functionally various information both at ZI level and at the level of mesencephalic structures studied in this work.

[The organization of diencephalic zona incerta projections to the structures of the pallidum in dog brain].

The detailed organization of the projections of the individual sectors of the zona incerta of the diencephalon to the functionally diverse pallidal structures in dog brain was investigated by the method of antero- and retrograde axonal transport of horseradish peroxidase. It was found that the neurons of the caudal incertal sector innervated the globus pallidus and the nucleus entopeduncularis which predominantly received the innervation from the motor structures. The projections from single neurons of the dorsal and ventral incertal sectors are directed to the same pallidal structures. No connections of the zona incerta with the limbic ventral pallidum were established.

[Basal ganglia projections to zona incerta of dog diencephalon].

Using the method of the retrograde axonal transport of horseradish peroxidase, it was determined that in dog, the projections from globus pallidus, nucleus entopeduncularis, substantia nigra and pedunculopontine nucleus were directed to all the regions of zona incerta. In the present study, no topical features were detected in the organization of these projections in dog, since after the injections of the marker in different regions of zona incerta, similar distribution of labeled neurons was observed in basal ganglia. The projections from the striatum to zona incerta were not found.

[Structural organization of the zona incerta in the dog diencephalon].

Zona incerta in dog diencephalon was studied by the methods of Nissl and Kluver-Barrera. As a result of this study, 5 individual sectors were identified on the basis of the analysis of fiber Organization, morphological types of neurons and the density of their distribution. The mapping of zona incerta was performed, and the borders of the sectors were accurately determined by histochemical demonstration of NADPH-diaphorase-positive neurons.

[Structural basis of the striopallidum and the pedunculo-pontine tegmental nucleus participation in organization of adaptive behaviour].

The method of retrograde axonal transport of peculiarities of the organization of afferent and efferent projection systems of separate substructures of the pedunculo-pontine tegmental nucleus and functionally various (motor and limbic) areas of the striopallidal structures allow to discuss the structural basis of carrying functionally diverse information and its integration in the basal ganglia system as well as in the tegmental region. The obtained morphological data prompts understanding of the morpho-functional basis of interaction of the structures under study and their participation in adaptive behaviour.

[Striopallidum projections to the pedunculopontine tegmental nucleus in the dog mesencephalon].

Using the method based on the retrograde axonal transport of the horseradish peroxidase, striopallidal afferent projections to the pedunculopontine tegmental nucleus (PPN) of the dog brain were studied. It was shown that the main source of these projections was pallidum, since the projections were directed both to the compact and diffuse parts of this nucleus from all its structures: nucleus entopeduncularis, globus pallidus and ventral pallidum. In the striatal complex, namely in the nucleus accumbens, only single labeled neurons projecting exceptionally to the compact part of the PPN, were detected Since in the distribution of the projection fibers, originating from the functionally various territorries of the striopallidum and directed to the individual substructures of the PPN, no topical elements were detected, the separation of the functionally specific (motor and limbic) regions in the PPN, on the basis of findings obtained, appears impossible.

[The organization of the efferent projections of the pedunculo-pontine tegmental nucleus to the dog pallidum ].

The study of pedunculo-pontine-pallidum projections in the dog's brain, which was performed using the method of retrograde axonal transport, has demonstrated the projections of a compact part (PPNc) and the lateral area of a diffuse part (PPNd) of midbrain pedunculo-pontine tegmental nucleus (PPN) to the globus pallidus, nucleus entopeduncularis and the ventral pallidum. PPNd medial area adjacent to decussation of the superior cerebellar peduncules, which is distinguished in other animals as the mesencephalic extrapiramydal area (MEA), projects only to the globus pallidus. In the dog, this tegmental area is not the major source of projections to striopallidum, therefore it appears not to be valid to distinguish it as an individual structure, it is reasonable to indicate only a topical organization PPNd projections to the pallidum. It was detected that the structures of pallidum received the projections from both cholinergic and non cholinergic initial PPN neurons.

[The organization of the efferent projections of the pedunculopontine tegmental nucleus to the striatum of the dog brain]. / Organizatsiia éfferentnykh proektsii pedunkulopontiinogo iadra pokryshki striatum mozga sobaki.

Using the method of retrograde axonal transport, the detailed study was performed to demonstrate the efferent projections of the individual substructures of the pedunculopontine tegmental midbrain nucleus to the functionally different segments of the striatal structures in the dog. The compact and diffuse parts of this nucleus were found to project to the segments of the putamen, caudate nucleus and nucleus accumbens which belong to both limbic and motor systems. The medial region of the diffuse part adjacent to the decussation of superior cerebellar peduncles (presumably midbrain extrapyramidal area), projected only to the dorsal segments of the caudate nucleus and the putamen belonging to motor system.

[Structural organization of pedunculopontine tegmental nucleus in the dog's midbrain]. / Strukturnaia organizatsiia pedunkulopontiinogo iadra pokryshki srednego mozga sobaki.

The aim of this study was to determine the borders of pedunculopontine tegmental nucleus (PPN) in the dog's brain and to describe its individual substructures on the basis of the cytoarchitectonic study of this nucleus. Using the methods of Nissl, Kluver-Barrera and histochemical demonstration of NADPH-diaphorase, which is a selective marker of cholinergic neurones of tegmental area, the analysis of fiber organization, morphological types of neurons and density of their distribution in PPN was carried out. As a result, mapping this nucleus in dog's brain was performed and the borders of its parts including a compact and a diffuse one were described. It was not possible to distinguish mesencephalic extrapyramidal area from the general composition of PPN.

[Morphological analysis of information processing in basal ganglia of mammals]. / Morfologicheskii analiz putei provedeniia informatsii v bazal'nykh gangliiakh mlekopitaiushchikh.

The article reviews published and own data on special features of organization of afferent cortical and infracortical correctional systems of the total striopallidaric nuclear complex in various species of mammals. The article focuses on analysis of organization of these flows in a dog being a classical object of behavioural experiments and a rare object of neuromorphological studies. It was discovered that the general trend towards segregated and converged flows of functionally different information at the level of striopallidum is retained in all tested mammals, being an evidence of the fundamental nature of the discussed principles of organization of the projection systems of basal ganglia. The reviewed morphological data confirm reliability of the presented concept of basal ganglia functioning.

[Organisation of thalamic projections of striopallidum in the dog brain]. / Organizatsiia talamicheskikh proektsii striopalliduma mozga sobaki.

The experiments, using the technique of double luminescent labelling, were performed to study the distribution pattern of labelled neurons in thalamic nuclei depending on location of injected luminescent label in functionally similar or functionally diverse areas of striopallidum in the brain of 16 dogs. The peculiarities found in the organization of canine thalamo-striopallidum projection system indicate high level of its specificity, as it was found that not only motor and limbic areas of striopallidum, but also its functionally related areas receive mainly, the separate inputs from different cell groups. The centromedian nucleus was found to contain the groups of diffusely mixed cells, containing double labelling, that innervate functionally different segments of nucleus caudatum. In the centromedian, parafascicular, central medial and mediodorsal thalamic nuclei, projection neurons form similar cell populations, innervating different segments of striopallidum structures, related to the single functional system. The same striopallidum areas receive projections from a small number of neurons by axonal collaterals.

[Analysis of the morphological substrate of information processing in the striatum based on organizational characteristics of its afferent projections]. / Analiz morfologicheskogo substrata obrabotki informatsii v striatume na osnove osobennostei organizatsii ego afferentnykh proektsii.

By the method of axonal transport of the retrograde markers, the afferent projections, coming from functionally different cortical and subcortical structures to various segments of the caudate nucleus, were investigated in the putamen and the nucleus accumbens of the dog brain. On the basis of the determined peculiarities of the spatail organization of these projections, the morphological aspects of the segregated and convergent conducting and processing of the information in the striatum, which underlie their functioning, were analyzed.

[Spatial organization of the thalamic projections in the dog striatum]. / Prostranstvennaia organizatsiia talamicheskikh proektsii striatuma mozga sobaki.

Using the method based on retrograde transport of markers injected into different segments of caudate and accumbent nuclei and putamen peculiarities of labelled neurons distribution in thalamic nuclei of the dog brain were studied. Zones of projection of motor and limbic thalamic nuclei and overlapping of terminal fields of fibres projection neurons of thalamic nuclei that function in different systems were demonstrated in the striatum. Comparative analysis of thalamostriatal projections organization in dogs, cats and monkeys allowed to reveal certain diversities in their construction as well as similarities.

[Analysis of structural basis of information processing in basal ganglia: spatial organization of the thalamo-striatal projections in the dog brain]. / Analiz strukturnoi osnovy obrabotki informatsii v bazal'nykh gangliiakh: prostranstvennaia organizatsiia talamostriatnykh proektsii mozga sobaki.

Distribution of neurones labelled in a retrograde way, studied in functionally different dog's thalamic nuclei, elucidated anatomical aspects of functional heterogeneity of the basal ganglia and of integrative information processing, as well as the organization of adaptive behaviour mechanisms.