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The results of comparative morphological and ultrastructural research of the synaptic organization of spinal cord motoneurons from fishes, amphibian, reptiles and mammals are presented in the review. Fundamental regularities of the formation of the synaptic organization of motoneurons in vertebrate phylogenesis were established. The results of electron microscopical analysis showed that all basic elements of the synaptic ultrastructure preserved in the motoneuronal synapse of vertebrates during the evolution. On the basis of large experimental material it was found that the synaptic organization of individual motoneuron as a whole underwent structural reorganization, presented as corresponding transformations in mechanisms of the synaptic transmission.

Studies have been made on the molecular weight and amino acid composition of albumin from the blood serum and liver, as well as on its content in liver extracts and in the blood serum of male rabbits at the age of 1, 30, 180, and 720 days. During postnatal life, quantitative changes in the amino acid composition of the proteins investigated take place, which are more significant in liver albumin than in serum albumin. Albumin content of the blood serum and liver extracts decreases at later ontogenetic stages (in 180- and 720-day animals), which is presumably associated with the decrease in synthesis of this protein by the liver. The molecular weight of the albumin remains constant in all age groups being typical for serum albumin of vertebrates.

Synthesis of peptides during polymerization of GlyNH2 and PheNH2 has been demonstrated by means of gel-chromatography and thin-layer chromatography. The optima of pH and temperature have been estimated for the reaction. Grem's salt, tripolyphosphate and pyrophosphate were shown to cause the stimulatory effect on the peptide formation, but there was no correlation between the yield of the peptides and the hydrolysis of the polyphosphates. On the basis of the experimental data, it has been concluded that hydrolysis of polyphosphates is not an energy source for the polymerization of GlyNH2 and PheNH2. Therefore, polyphosphates cause catalytic effect on the peptide synthesis from the amides of amino acids in homogeneous medium.

In recent years the identification of regulatory mechanisms of the general adaptation syndrome, manifesting itself as the response of an organism to drastic changes in the environment and leading to emotional stress, acquires a special significance. The control over visceral functions plays a particular role in stress reactions because of emerging threat of violation of neurodynamic balance of sympathetic-para- sympathetic relationships with their most sensitive element - the heart. Quick adaptation to stress helps to restore not only the sympathetic-parasympathetic homeostasis but also the energy metabolism. One of the essential components, activating metabolic processes, is taurine. This paper considers the descending influence of the paraventricular nucleus (PVN) on neuronal reactions of the solitary tract nucleus (NTS), the first linking pathways of visceral sensitivity, the mechanisms of central control over visceral reactions by mathematical model analysis of heart rate variability (MMA HRV) as well as morpho-histochemical changes in brain structures integrating and regulating the visceral sphere (PVN of the hypothalamus and the amygdala) under psycho-emotional stress without and with intraperitoneal injection of taurine (50 mg/kg). Acute and semichronic experiments were conducted on white nonlinear rats under 5-hour- long immobilization psycho-emotional stress. A highly defined centralization of vegetative HRV parame- ters (HR, IVR, INRS) was revealed, these parameters being normalized on days 7 and 14 at the background of taurine injections. The interaction and interdependence of the central regulatory mechanisms of cardiovascular reactions are shown as well as a considerable protective effect of taurine on promoting early restoration of adaptive properties of the central and peripheral segments of visceral sensitivity under development of long-term psycho-emotional stress.

This paper reviews various aspects of the physiological and biochemical mechanisms directed to create special rheological conditions for blood flow called <> blood properties. The struc- tural features of the phospholipid composition of plasmatic membranes and cytoskeleton, the state of the intra- and extracellular ATP pool, ATPase ecto-enzymatic activity of nucleated and non-nucleated red blood cells of vertebrates are compared and thermal effects in nucleated erythrocytes investigated. A hypothesis based on literature and own data is suggested according to which the phenomenon of <> blood properties relies on a decrease in the relative viscosity of blood due to the thermal hydrolysis of extracellular ATP excreted by erythrocytes on their surface particularly strong during deformation stress in capillaries. We belive that in fish an important role in this process may belong to ecto-ATPases of erythrocyte plasmatic membranes. Due to generation of heat by the hydrolysis of extra- cellular ATP, the wall layer of the plasma appears to warm up. This could change the structure of the membrane bilayer and deform the cytoskeleton, thus providing the special rheological conditions for blood flow. Among the proofs of possible existence of this mechanism is heat production ability of nucleated red cells in fish revealed in our stymies.

Sleep is characterized by cycling and consecutive alternation of different phases and stages, each of them featuring intrinsic changes of vegetative regulation with oscillations of heartbeat rate that may cause development of cardiac rhythm disorders especially under presence of concomitant somatic diseases. This paper deals with the problems of interrelationships between disturbances of heart conduction and obstruc- tive sleep apnea. It is shown that some mechanisms of the occurrence of brady-arrhythmias (first of all, features of vegetative regulation with increasing parasympathetic tone) under sleep arrests are inherent to human divers as well as to mammals conducting water or near-water way of living associated with forced breathing delays at diving and prolonged staying under water. These mechanisms may carry out defense function.

The paper deals with study by the method of solid-phase indirect immunoenzyme analysis of levels of the novel serotonin-modulated anticonsolidation protein (SMAP) that is directly correlated with serotonin level as well as of biomarker cytochrome P-450 in the liver, gills, and brain of the eastern alburnoid (Alburnoides bipunctatus eichwaldi) caught in the rivers Khudat, Akstafachai, Kura, and Araks flowing at the territory of Azerbaijan. There was revealed a marked downregulation of cytochrome P-450 and SMAP in the liver and gills of the fish caught in the Akstafachai River relatively to values in the fish from the Khudat River not contaminated with pollutants. In the liver and gills in the fish from the Kura and Araks rivers, a significant differently directed changes of the cytochrome P-450 and SMAP levels were observed: downregulations of the cytochrome P-450 versus an upregulation of SMAP. In the brain of the fish from the River Akstafachai there was observed some downregulation of cytochrome P-450, whereas in fish from the Kura and Araks rivers--a significant upregulation of the SMAP level. The obtained results are analyzed from standpoint of processes of adaptation and disadaptation of aquatic organisms to impact of pollutants.

In this paper we present results of a comprehensive analysis of the effect of heat shock at different stages of ontogenesis (adult stage, development of the mushroom bodies and the central complex) on courtship behavior (latency, duration and efficacy of courtship), sound production (pulse interval, dispersion of interpulse interval, the percentage of distorted pulses, the mean duration of the pulse parcels), learning and memory formation compared with the content of isoforms LIMK1 in Drosophila melanogaster male with altered structure of the limk1 gene. The heat shock is shown to affect the behavior parameters and LIMK1 content in analyzed strains of Drosophila. The most pronounced effect of the heat shock was observed at the stage of development of the central complex (CC). Heat shock at CC and adult restores the ability of learning and memory formation in the mutant strain agn(ts3), which normally is not able to learn and form memory. Correlations between changes of content of isoforms LIMK1 and behavioral parameters due to heat shock have not been established.

The paper is a review of literature data on interaction of the mammalian erythrocyte acetylcholinesterase and blood serum butyrylcholinesterase with a group of isomer complex ester derivatives (acetates, propionates, butyrates, valerates, and isobutyrates) of bases and iodomethylates of ephedrine and its enantiomer pseudoephedrine. For 20 alkaloid monoesters, parameters of enzymatic hydrolysis are determined and their certain specificity toward acetylcholinesterase is revealed, whereas 5 diesters of iodomethylates of pseudoephedrine were hydrolyzed only by butyrylcholinesterase. The studied 20 aklaloid diesters and 10 trimethylammonium derivatives turned out to be non-competitive reversible inhibitors of acetylcholinesterase and competitive inhibitors of butyrylcholinesterase. The performed for the first time isomer and enantiomer analysis "structure-efficiency" has shown that in most cases it is possible to state the greater comlementarity of the catalytical surface of enzymes for ligands of the pseudoephedrine structure, such differentiation being realized more often at the reversible inhibition of enzymes. pseudoephedrine.

The paper presents results obtained at recording under conditions of stresses of different character of activities of enzymes (tyrosinase, DOPA-oxidase, acetylcholinesterase) and level of the catecholamine content in tissues of head and fat body of imago and larvae of housefly from lines with different lifespan. A suggestion is put forward about different mechanisms mediating photoperiodic regulation of metabolism in individuals with different intensity of metabolism.

A possibility of correlative formation in ontogenesis of central mechanisms of stereognosis and speech function is considered in the paper by example of comparison of changes in spatial organization of interregional interaction of various cortex areas in children of three ages (5-6, 7-8 and 9-10 years) and in adult examinees during their performances of stereognostical, verbal-mnestical and motor manual activity (tepping-test). With age dynamics of children there is observed a significant increase of the degree of similarity of the spatial structure of EEG interrelations characteristic of periods of performance of stereognostical test with patterns of changes of the EEG distant connections revealed at performance of speech tasks. In turn, the similarity of patterns of interregional EEG relations characteristic of stereognostical tasks with the patterns revealed at the periods of performance of the tepping-test is not increased with age. On the whole, the obtained data allow believing that with increase of children's age there rises the degree of topological similarity of the spatial structure of systemic interactions of the cortex zones, on which there are "supported" processes of realization of stereognostical and speech functions. Progressing increase with children's age of the degree of similarity of distributive organization of neurophysiological mechanisms of central provision of the speech and stereognosis functions can indicate in favor of concept of correlative formation of these higher psychical functions in postnatal ontogenesis. The obtained results show that the correlative interfunctional interactions promoting progressive development of cognitive functions in the child ontogenesis can be realized through long fiber associated and commissural pathways composing the morphofunctional longitudinal-transversal "skeleton" ofneocortex in the close interaction with thalamo-cortical integrative systems.

In 46 male and 19 female students who were both donors and recipients of scent samples, we studied effects of the menstrual cycle phase, reproductive health, sexual motivation, and sexual experience on subjective assessment of intensity and pleasantness of the sweat scent. The sweat samples were collected by the 60-min long exposure of a filter paper in the armpit. Then the male and female samples were reciprocally assessed olfactorily with respect to their intensity, unpleasantness/pleasantness, and association with male or female. It has been established that the cycle phase affects statistically significantly the coincidence of subjective assessments by the unpleasant/pleasant scale, which different recipients were giving to the same scent samples. Their coincidence in the non-receptive state is replaced by the non-coincidence at the receptive cycle phase, which indicates an increase in the contribution of the recipient's individual properties to the variability of scent assessments. In girls in the non-receptive state there is noted the reverse correlation between the strength and pleasantness of the male scent. In the receptive state, they become tolerant to intensive male scents. At non-regular menstrual cycles, the female scent is assessments by young males as less pleasant. At the same time, the girls themselves with the cycle disturbances assess higher the male scent samples as compared with reproducibly healthy girls. The first sexual experience decreases the subjective assessments given by girls to the male scent samples. The young males, on the contrary, increase assessments given by girls to the male scent samples. The young males, on the contrary, increase assessments of the female scent on having acquired the sexual experiment. Coefficients of correlation of the mutual assessments of scent pleasantness of young males and females are progressingly rising with increase of biological and social significance of the search for optimal partner. Thus, effect of psychophysiological and social factors on assessments of pleasantness of scent samples aggress well with requirements, to which the reproductively significant non-verbal signal should fit.

This paper refers us to the mid-1960s, when mechanisms of the animal rhythmic activity were vividly discussed and the concept of "generator of rhythm" was formulated. Since at than time the device of the generator of rhythm was understood very poorly, V. Menshutkin, V. Svidersky, and A. Umnov, by the example of an insect (locust), attempted to develop the first mathematical model generating rhythm of the flight. Why the interest in such model arose, how it was created, and what the result of it was has been described in this paper.

The paper considers various aspects of glial sheaths of neuritis in the crayfish peripheral nerve trunks and roots. There are revealed dotted glio-neurite tight junctions and a varicose deformation of the intercellular glio-neurite cleft. Rupture of membranes in the area of contact leads to formation of the glio-neurite pore (less than 10 nm) that is enlarged and forms wide (up to 240 nm) syncytial perforations. At the edge of perforation, either remnants of tight junctions are present or damaged membranes that fuse and are rounding. The lumen of perforations always contains residual membranous bodies in the form of vesicles. Their deviation from the median line can indicate a mutual translocation of substances of the glio- and neuroplasm. In the adjacent layers of the multilayer glial sheath there is noted a similar phenomenon of formation of the glio-glial syncytial connection terminating by fusion of neighbor glial layers, which is terminated by fusion of neighbor glial layers into the single lamina. The process begins from the varicose deformation of interglial clefts, which appears as a result of massive formation of dotted and expanded tight membranous contacts. As a result of transformation of ellipsoid varicose deformations into the spherical ones, syncytial pores (less than 10 nm) between them are formed, which are enlarged and break the paired gliolemmas into fragments. As a result, the adjacent glial layers are united. Since this process in intact animals occurs on the background of undamaged nerve structures, a suggestion is put forward about its reversibility and the functional nature.

This paper is a continuation of our first paper ""Zonal model" of description of homeostasis" [1] that discussed some general regularities of the organism functioning connected directly with maintenance of homeostasis. It might seem that consideration of such general issues could have been only of theoretical interest; however, for the recent years, a trend has been formed in direction of cholistic physiology and medicine when there are considered first of all the organism functioning regularities responding for maintenance of its integrity in norm and in pathology. A particular attention in the present paper is paid to consideration of multifunctional possibilities of organs and functional blocks. In our opinion, such analysis can promote solution of general problems of physiology and medicine and provides a possibility to better understand organization of processes in the organism throughout the lifespan as well can help in elucidation of causes of some chronic diseases.

The paper deals with a comparative study of various aspects of reactivity (substrate and inhibitor specificity, sensitivity to action of hydrophobic organophosphorus inhibitors, capability for reactivation) of preparations of the brain, erythrocyte, and serum cholinesterases of a group of mammals (human, rabbit, rat, cattle, dog, and cat). It has turned out that at preservation of the species and tissue specificity, catalytic properties of cerebral and erythrocytic cholinesterases of the same animal species are very close to each other.

In this review, causes of tremendous differences in respiration and oxidative metabolism between the homoiothermal and poikilothermal vertebrates are discussed. Tissues of the latter contain not lower, and sometimes even higher amount of mitochondria with the powerful potential of oxidative enzymes, as compared with the homoiothermal vertebrates; this potential is realized only by 3-4% because of a low rate of oxygen transport due to peculiarities of the cardiovascular system of the lower vertebrates. Limitation of ATP synthesis is responsible for a specific structure of plasma membranes with the essentially lower amount of channels for the passive ion leakage as compared with the mammalian plasma membranes. Examples are presented of the homoiothermal animal cells (the frog olfactory receptor cell) that contact with environment without mediation of the blood circulation system and have the energy metabolism level comparable with that of mammalian cells. Examples of energetic aromorphosis are tunas with heat exchangers in several organs and with a powerful system of oxygen delivery to cells; owing to this, intensity of their oxidative metabolism could reach that of the higher terrestrial vertebrates. The closing part of this paper describes the molecular mechanisms that allow some representatives of reptiles, amphibians, and fish to survive long periods of hypoxia and anoxia.

Evolutionary physiology as independent direction of physiology was formed in the XX century and was rapidly developing in its second half. To evaluate some tendencies of this process, we analyzed publications in Journal of Evolutionary Biochemistry and Physiology, one of the leading specialized periodicals on this problem. Analysis of works published for 4 decades has shown that the majority of papers deals with study of evolution of function of the nervous system (40-60 papers per year), less papers concern study of functions of sensory and visceral systems (20-30 per year). Among the used method, the most widely spread is the comparative-physiological method. By the end of the 1990s the number of works with use of methods of embryophysiology decreased. In the performed studies, predominant are physiological methods. Use of biochemical methods decreased, while of methods of molecular biology increased. The most often used objects of studies were mammals. By the end of the XX--beginning of the XXI century, in the greater number of papers the object of study has become human, while the number of publications in which experiments were performed on amphibians, reptiles, and birds decreased. More than a half of all works were carried out in St. Petersburg (Leningrad); the number of papers submitted from Moscow institutions gradually decreased, but the number of works from regions of Russia rose. Most studies were performed at institutes of the Russian Academy of Sciences and universities, while the number of papers from institutes of the Russian Academy of Medical Sciences decreased. For the last few years, several generalizations on evolution of functions and functional evolution have been formulated; handbooks and monographs on problems of evolutional physiology have been published.

The paper deals with antimutagenic body activity and its underlying mechanisms. The experiments carried out on the one-year old sturgeons (Acipenser gueldenstaedti persicus) and goldfish (Carassius auratus) have shown that intramuscular administration of serotoninmodulated anticonsolidation protein (SMAP) leads to a twofold decrease of erythrocyte mutagenic alterations (the micronuclear test, p < 0.01) caused by action of benthic deposits (0.8 ml/l, 3 days) polluted with industrial wastes. Exposure of goldfish in water contaminated with oil (500 mg/l, 3 days) led to a sharp rise of the content of the 70 kDa brain protein fraction (p < 0.001); these water-soluble proteins are assumed to belong to heat shock proteins (HSP). At the same time, in the brain of the studied animals there was observed a simultaneous increase of the SMAP content (p < 0.001). After 3 h, intracerebral SMAP administration to goldfish increased significantly the 90 kDa protein fraction content (p < 0.01), probably HSP90, in the electrophoretic profiles of the brain water-soluble proteins. Thus, the obtained results indicate that the body serotoninergic system has the antimutagenic activity providing protection of cells from action of harmful environmental factors by an enhancement of synthesis of proteins suggested to belong to HSP.

Molecules of secretory immunoglobulins (Ig) of classes A and M (sIgA and sIgM) play the main role in protection of mucosae from pathogenic factors. The apparatus of synthesis of these molecules represents the most powerful part of the immune system. One of the key elements of the sIgA and sIgM is J-chain. It represents an acid polypeptide of molecular mass of about 15 kDa composed of 137 amino acid residues including 8 cysteine residues and one site of N-glycosylation. The primary structure of the J-chain is unique: attempts to ascribe it to any family of known proteins so far have failed. The J-chain is inserted into the sIgA and sIgM molecules to form disulfide bonds with C-terminal sites of alpha- or mu-chains. It is necessary for formation of IgA dimers and IgM pentamers, for reception of these molecules by epithelial cells, binding of secretory component to them, and for transfer of sIgA and slgM molecules onto mucosal surfaces and into secrets of endocrine glands. The J-chain has been revealed in the cytoplasm of the early T- and B-lymphocyte precursors not producing Ig. The J-chain is detected in the human embryonic liver cells earlier than the expression of the mu-chain gene begins. Study of mice with knockout of J-chain B-lymphocytes-producents has shown their block of function of T-helpers providing formation of immunologic memory. Comparison of J-chain genes of mammals, amphibians, reptiles, and cartilaginous fishes has shown the degree of interspecies homology of these proteins to vary from 33% to 70%. The J-chain genes were revealed in representatives of all vertebrate classes except for cyclostomes and bony fishes. In 1996, data were published about the presence of the J-chain genes-homologs in invertebrates, tunicates, and cyclostomes. No papers reproducing or confirming these data have been published. On the contrary, in the literature an opinion appeared that indicate necessity to revise the notion about the presence of J-chain in invertebrates. The main unsolved issues on the J-chain involve the tertiary structure of this protein, its relation to some particular protein family, its functions in cells of the T- and B-lymphocytic differentiation lineages as well as its evolutionary age.

Changes of environment parameters produce essential effects on the serotonergic system activity in the body tissues. This paper describes study of the serotonergic system activity in various tissues of half-migratory fish - the Caspian roach Rutilus rutilus caspicus and the bream Abramis brama orientalis - caught in the fresh and brackish water. Using the method of indirect solid-phase ELISA test, the serotonergic system activity was assessed by determining in the studied fish tissues of the amount of serotonin-modulating anticonsolidation protein (SMAP) that is in the linear correlation with serotonin level. A significant change of the SMAP level in the Caspian roach and bream brain was found under effect on increased water salinity. Analysis of the SMAP amount in the bream liver did not reveal any differences in the animals caught in the brackish and fresh water. At the same time, in the bream gill there was a small rise of the SMAP content in the fish caught in the brackish water. The revealed in this experiment elevation of the SMAP amount in the Caspian roach and bream brain reflecting a corresponding increase of the serotonergic system activity indicates involvement of adaptive readjustments in the animal body.

Background activity of brain cortex neurons in ontogenesis appears very early, soon after completion of their migration. At the moment of its appearance, the background has several peculiarities, the most characteristic of which are its episodic character and synchronous fires of adjacent neurons forming domains. This paper considers mechanisms determined the appearance and the most characteristic peculiarities of the background of cerebral cortex neurons in ontogenesis.

The antienzymic activities of 14 organophosphorous compounds, the derivatives of dialkyl thiophosphoric acid, towards the acetylcholinesterase (AChE), butyrylcholinesterase (BuChE) and carboxylesterase (CE) from the spring grain aphid and mammals were investigated. The dependence of inhibitory activity of the compounds on their alkyl radical length was shown to be different for the AchE from the aphid and man. Some less pronounced differences in this dependence were revealed between the BuChEs from the aphid and horse as well as between the CEs from the aphid, mouse and red spider mite. The data give evidence of a distinction in structure of the active surfaces of the enzymes from the aphid and mammals. Some peculiar properties of the aphid cholinesterases are discussed taking account of the results of the present and previous papers.

Reaction of spontaneous periodic motor activity (SPMA) to exogenous increase of catecholamine (CA) level in brain by means of L-DOPA injection or other methods of catecholaminergic system activation undergoes quite essential changes in process of early postnatal ontogenesis. Possible causes of such age changes are considered in present paper: 1) increase of SPMA reactivity to CA level change; 2) heterochronic development of dopamine- and adrenergic systems; 3) heterochronia in maturation of SPMA activation and inhibition mechanisms; 4) maturation of its regulation levels. It was shown that activation of catecholamine systems resulted in changes of SPMA levels in the same direction as its natural age dynamics occurred: enhancement in growth period on the first week after birth, and subsequent decrease of activating and appearance of inhibitory effects in period of SPMA age inhibition.

Electron microscopic studies on the spinal motor nuclei in amphibians indicate significant diversity in chemical synapses formed on motoneurones by axonal endings of supra- and intraspinal systems. High ultrastructural specialization was observed among axosomatic, axodendritic and axoaxonal synapses. Several types of axo-spine synapses and axodentritic synaptic complexes of the "glomerular" type were revealed. New data on ultrastructural peculiarities of chemical synapses presented in this paper, together with earlier detailed data on morphologically mixed and electrotonic synapses, increase our knowledge of evolutionary trends in synaptic organization of motoneurones in the spinal cord and suggest the existence of a complex mechanism of integration of synaptic influences in the spinal cord of lower vertebrates.

In rats ageing up to 3 weeks, studies have been made on the reactions of the spinal motor center to long-lasting rhythmic stimulation of sensorimotor cortex. It was found that in 5-day old rats specific periodic pattern of the activity may be recorded similar to the autorhythmic spontaneous activity described in our earlier papers. In older animals periodic pattern of reaction can also be observed, but it may be modulated by stimulation. Beginning from the 12th day, periodic pattern of reaction is transformed into aperiodic one typical for adult animals. From the 3rd week of life, the inhibitory effect of motor cortex stimulation on locomotor activity could be observed.

By means of UV-spectroscopy, gel filtration, thin layer and paper chromatography, it has been shown that the action of UV irradiation and heat on a dry mixture of nitrogenous bases and deoxyribose results in the formation of nucleoside pool, particulary deoxyadenosine. These energy sources were chosen in order to imitate at least approximately the conditions assumed to exist on the primitive Earth. Similar synthesis takes place in the atmosphere of the three gases studied, being more intensive in CO2 than in N2 or O2.

In the paper we consider some aspects of evolution of actin, myosin, and Ca2+-binding proteins regulating their interaction. On the basis of the data recently obtained, we propose the following theses: 1. All types of motility in the living world where actin and myosin are involved, are based on active sliding of actin filaments along myosin filaments (or less organized myosin aggregates). 2. Ca2+-sensitivity of actin-myosin interaction is as old as actin and myosin themselves. Therefore, Ca2+-independent actomyosin ATPase found in vitro does not correspond to physiological sutuation and in this sense relfects an experimental artefact. 3. All proteins which regulate Ca2+-sensitivity of actin and myosin interaction, contain EF-hand structure. 4. It is generally believed that non-muscle cells, including Protozoa and Myxomycetes, contain all regulatory mechanisms which were described for muscles. However, in our opinion, troponin complex similar to that found in striated muscles, if present does not operate there.

Electroolfactograms were recorded in isolated olfactory epithelium of pigs, both females and castrated males, of various age. The boar pheromone, 5 alpha-androst-16-en-3-one, elicited negative electrical responses up to 2 mV in many preparations. The threshold response corresponded to as low as 10(-9) g of the pheromone on a filter paper. The specific anosmia to the boar pheromone was discovered in few preparations, where responses to the pheromone were absent and the sensitivity to common odour substances (butyl acetate, camphor, butyric acid, etc.) was unchanged.

The paper presents data on the directional selectivity of hearing in the bottlenose dolphin as a function of masking noise angle. It has been shown that the hearing system of dolphins is characterised by sharp lowering of masked thresholds depending on the noise going in the high frequency region. The same effect is shown in man, but not so evidently.

The paper provides comparative characteristics for different types of electrically operated ionic channels in the neuronal membrane of invertebrate (molluscs) and vertebrate (rats) animals. It was shown that ion-selecting characteristics of sodium channels are identical for all the investigated membranes. In addition, main selective filter of calcium channels also possesses a similar characteristic; apart of it they have an external binding group which prevents the influx of monovalent cations into the channel and thus maintains its selectivity towards divalent cations. A natural intermediate modification of ionic channels is found, which has no such external binding group. There are two different mechanisms of maintenance of electrically operated ionic channels in a functioning state--a metabolically-independent and metabolically-dependent one. In the latter case in order to preserve the ability of the channel for activation, it is essential to maintain a certain level of cAMP inside the cell which determines, in turn, the presence of corresponding membrane proteins in a phosphorylated state. This mechanism of regulation of the function of electrically operated ionic channels is also identical in both invertebrate and vertebrate membranes. It is suggested that the molecular structures providing the electrical excitability represent the most ancient product of evolution used for the generation of basic forms of nervous activity in all types of nerve cells of existing animal species.