[Erythrocytes of hetero- and homoiothermal animals in natural and artificial hypothermia].

By the low-angle light scattering technique there are revealed peculiarities of dynamics of transformation (osmotic fragility, level of hemolysis and ratio of forms by index of sphericity) of erythrocytes of hetero- (golden hamsters Mesocricetus auratus) and homoiothermal (white rats Rattus norbegicus) animals in natural hibernation and suspended animation, craniocerebral and immersion hypothermia. In control in hamsters the osmotic fragility and the level of hemolysis of erythrocytes were higher than in rats, predominant were modified forms (in particular stomatocytes). Under artificial hypothermia, regardless of the way of achievement, depth and duration, we observed changes similar in direction, but different in expression: the osmotic fragility and hemolysis increased, the portion of discocytes decreased (especially sharply in hamsters under suspended animation), the number of changed erythrocytic forms rose. In contrast, under hiberation the osmotic fragility, hemolysis and the amount of stomatocytes declined, the portion of discocytes increased, but at the same time the amount of prehemolytic forms (spherocytes) rose too. In 24 hs there occurred a decrease of osmotic fragility (after suspended animation more pronounced in hamsters) and the level of hemolysis (especially after immersion hypothermia), the portion of discocytes was restored, in hamsters after suspended animation and in rats after immersion hypothermia it even exceeded the control level; spherocytes in blood of hamsters were not revealed, in rats they were elevated. Possibly, the observed qualitative change of population of spherocytes 24 h after hypothermia toward its homogeneity is determined not only at the level of elimination of old and defected cells, activation of erythropoiesis, the appearance of highly resistant erythrocytes, but also at the level of time membrane-stabilizing mechanisms.

[Effect of different types of cold acclimation on osmotic fragility and sphericity index of rat erythrocytes].

The effect of different types of cold exposures, long-term and rhythmically organized (RCE), which increased organism adaptive ability to cold, on osmotic fragility and sphericity index of rat erythrocytes were studied. It is shown that depending on the type, intensity and duration of cold exposure the change of sphericity index occurred. More over, RCE1 (exposure temperature -12 °C, during 2 days) led to the increase in osmotic fragility, but RCE2 (exposure temperature 10 °C, during 2 days), RCE3 (exposure temperature 10 °C, during 1 month) and long-term (exposure temperature 5 °C, during 1 month) - to membrane modification without change in its osmotic fragility.

[Chaotic non-linear dynamics of alpha-band of the EEg and organization of the cortical activity of P300 wave].

Variations of non-linear dynamic operations in of alpha-band of the EEG are reflected in the peculiarities of the P300 wave cortical field organization. In high-dimensional chaotic processes this field is characterized with high values of integral indices of its activity, the spatial synchronization of generating process as well as with the prevalence of P3a wave generation. The diversity of spatial combinations of P-wave sources reflects the high rate of their spatial complexity organization. The main contribution into this activity is made by symmetrical points of anterior and temporal cortical portions. In low-dimensional dynamics the spatial structure of the positive wave is simplified. It becomes less global and more differentiated. P3b wave generation prevails in this case. The values of integral indices of wave cortical field activity are reduced. The focal topography of positive waves and their sources changes. Chaotic systems of alpha-band wave generators demonstrate good controllability and high plasticity in contingent acoustic stimulation. They change their dynamic characteristics due to biofeedback control, determining thereby P-wave field organization.

Temperature-dependent changes in erythrocytes' cytosol state during natural and artificial hypobiosis.

At present, the question of how the structural state of the erythrocyte cytosol is arranged to maintain essential permeabilities successfully both at normal temperature and during periods with a significant body temperature reduction during hypobiosis remains unanswered. In the present work, we performed comparative investigations of temperature-dependent changes in the cytosol state of erythrocytes from animals subjected to natural (winter hibernating ground squirrels) or artificial hypobiosis. The cytosol state was evaluated by the ESR method of spin probes (TEMPON) within the temperature range of 0-50 degrees C. Erythrocyte resistance to acid hemolysis, which is limited by the permeability of membranes for protons and the state of the anion channel, were determined using the method described by Terskov and Getelson [Biofizika 2 (1957) 259]. A change in cytosol microviscosity of erythrocytes was found as well as a temperature-dependent increase in acid resistance of erythrocytes. Our investigations allow us to conclude that physiological changes occurring in a mammalian organism during natural and artificial hypobiosis are accompanied by structural modifications of the erythrocyte cytosol. The temperature range where these modifications are observed (8, 15, 40 degrees C) suggests that the most probable modifying link is spectrin and/or the sites of its interaction with membrane. The interaction of cytoskeletal components with the cell membrane plays a key role in regulation of membrane permeability, suggesting an important role of this interaction in the adaptive reactions of erythrocytes.

[Proteinase-proteinase inhibitor system in aged rats with stimulated hypertension exposed to cord blood]. / Sistema proteinaza-ingibitor proteinaz u starykh krys so stimulirovannoi gipertenziei pod vliianiem kordovoi krovi.

The proteinases, nontrypsinlike proteinases (NTLP), alpha-1-proteinase inhibitor, alpha-2-macroglobulin (alpha-2-MG) activities were researched in serum, tissues of hypothalamus, cerebral cortices, lung, heart, liver, kidneys in old rats with hypertension caused by electricity current at introduction of cord and mature blood preparations. The increase of proteinase and NTLP activities were revealed on the background of alpha-2-MG level reduction. The changes caused by stimulated hypertension, can be corrected by introduction of blood preparations and the effect of cord blood is more manifested.

[Chaotic nonlinear dynamics of prestimulus EEG and the structure of auditory evoked potentials ]. / Khaoticheskaia nelineinaia dinamika prestimul'noi EEG i struktura slukhovykh vyzvannykh potenthialov.

The dynamic pattern of a prestimulus EEG was studied by the fractal analysis technique. The character of this pattern was shown to affect the structure of cortical auditory evoked potentials (EP). A monoperiodic pattern in the control frequency band was accompanied by a formation of several new attractors with low dimensionality attributed to simultaneous functioning of several weakly connected dynamic systems with an indefinite trend of a leading process. During development of multiperiodic processes in EEG segments, the fractal analysis revealed a tendency for a formation of a single complex dynamic system with high dimensionality of the attractor. Characteristic changes in parameters of the primary and middle-latency EP components, their correlation, and factor models are related with the character of nonlinear patterns. Analysis of variance revealed the most effective role of pattern changes in the EEG alpha control band. The structure of combination of parameters of the EP primary components into connected complexes depends on the nonlinear prestimulus EEG patterns. The above predictors determine differently directed and differently pronounced changes in parameters of the middle-latency positive waves.