[THE METHOD OF ANALYSIS OF Y-NEURON POPULATIONS IN THE LATERAL GENICULATE BODY OF THE CAT].

The paper presents a method of analysis of cell populations that combines the use of normalized spatial coordinates of the neurons with the morphometric criteria of their evaluation. These algorithms were applied to check the heterogeneity of apopulation of neurons Y-conducting channel in cat at the level of the lateral geniculate body (LGB). As a specific marker of Y-neurons, SMI-32 antibodies were used. Evaluated The dynamics of the distribution of the number of cells and the orientation of their soma within each layer and mediolaterally along the length of LGB dorsal nucleus (LGBDN). Among the SMI-32-positive neurons, the existence of at least two populations was detected differing in number, orientation and distribution of the soma in different layers of LGBDN. The heterogeneity of Y-neuron population in LGBDN detected in this study is consistent with the earlier electrophysiological data. We believe that the described algorithm for neuronal analysis may be successfully applied to study not only LGB, but also other extensive structures of the brain, including those having laminar organization.

[The method of the superposition of visual space map on a three-dimensional model of the cortical visual center of the analysis of the object motion].

The aim of the present investigation was to develop an algorithm of superposition of retinotopic map of PMLS (posterior medial part of lateral suprasylvian sulcus) visual area on a 3-D model of brain frontal slices. A step by step description of the algorithm is presented. The suggested algorithm may be used for the solution of the various tasks of the analysis of the organization of interneuronal connections.

Simultaneous bidirectional hindlimb locomotion in decerebrate cats.

We show that epidural spinal cord stimulation can elicit stable bidirectional locomotion of decerebrate cats on a split-belt treadmill. The stepping pattern of one limb was similar to unidirectional forward walking and, the other-was similar to unidirectional backward walking. This confirms that spinal and brainstem circuitry are sufficient to control such complex and extraordinary motor tasks driven by somatosensory input. Interlimb coordination during forward and backward walking was preserved in 2 out of 4 animals during 'extreme' conditions when one of the treadmill belts was stopped. Bidirectional locomotion worsened but was still possible after temporary spinalization by cooling the spinal cord on a low thoracic level. These present evidence for the great degree of the automatism for this stepping mode defined by the spinal neuronal networks.

Role of the trace amine associated receptor 5 (TAAR5) in the sensorimotor functions.

Classical monoamines are well-known modulators of sensorimotor neural networks. However, the role of trace amines and their receptors in sensorimotor function remains unexplored. Using trace amine-associated receptor 5 knockout (TAAR5-KO) mice, that express beta-galactosidase mapping its localization, we observed TAAR5 expression in the Purkinje cells of the cerebellum and the medial vestibular nucleus, suggesting that TAAR5 might be involved in the vestibular and motor control. Accordingly, in various behavioral tests, TAAR5-KO mice demonstrated lower endurance, but better coordination and balance compared to wild-type controls. Furthermore, we found specific changes in striatal local field potentials and motor cortex electrocorticogram, such as a decrease in delta and an increase in theta oscillations of power spectra, respectively. The obtained data indicate that TAAR5 plays a considerable role in regulation postural stability, muscle force, balance, and motor coordination during active movements, likely via modulation of monoaminergic systems at different levels of sensorimotor control involving critical brain areas such as the brainstem, cerebellum, and forebrain.

[CAT'S VISUAL AREA 18 INTERMODULAR INTERACTIONS DEVELOPMENT UNDER DIFFERENT VISUAL ENVIRONMENT].

Primary visual cortex contains a set of modules, and their postnatal development depends on a combination of internal genetic and external (defined by visual environment) factors. In order to examine a development of intermodular interactions in visual cortex of kittens subjected to rhythmic light stimulation (15 Hz and 50 Hz frequencies, groups RLS-15 and RLS-50), we investigate an intermodular signal correlation by mean of optical imaging technique. Data was compared with control kittens and with kittens reared with no visual experience in total darkness (group DARK). A significant reduction of the intermodular correlation coefficient was obtained in the group RLS-15; the correlation coefficient values in the groups RLS-50 and DARK was not affected. Thus 15 Hz rhythmic light stimulation during sensitive periods of development disrupts an efficacy of intermodular neuronal connections.