Visnyk of Dnipropetrovsk University. Biology, ecology

3-7

Authors: I. О. Shmarakov, V. L. Borschovetska, М. М. Мarchenko

Development of the most of pathological conditions occurs by free radical mechanism which is characterized by increased free radical production at the cellular level, especially reactive oxygen and nitrogen species (ROS/RNS). The main producers of reactive oxygen species are, first of all, membrane bound NADH-dependent mitochondrial and NADPH-dependent endoplasmic reticulum electron transport systems, cytosolic oxidoreductase enzymes and multienzyme complexes. The aim of the study was to determine the features of generation of superoxide anion radical (O2·) as the primary reactive oxygen species, and nitric oxide (NO·) under conditions of thioacetamide-induced hepatotoxicity. The features of NAD(P)H-dependent gen-eration of superoxide anion radical (O2·) as the primary reactive oxygen species, and nitric oxide (NO·) in subcellular (mitochondrial, microsomal and post-microsomal) fractions of C57BL/6J mouse liver cells isolated by the method of differential centrifugation were determined under conditions of thioacetamide-induced hepatotoxicity and supplementation with pharma-cological doses of vitamin A. It was found that the development of acute hepatotoxicity induced by single intraperitoneal ad-ministration of 500 mg/kg of thioacetamide was accompanied by increased intensity of superoxide anion radical and nitric oxide production in microsomal and cytosolic fractions of liver cells, but not in mitochondrial fraction. Consumption of the pharmacological doses of vitamin A (3000 IU) has no hepatoprotective effect, however, it enhances the production of reactive oxygen and nitrogen species in the liver during acute hepatotoxicity.

19-32

Authors: V. V. Schwartau, P. A. Virych, T. I. Makoveychuk, A. Y. Artemenko

The paper gives the review on the role of calcium in many physiological processes of plant organisms, including growth and development, protection from pathogenic influences, response to changing environmental factors, and many other aspects of plant physiology. Initial intake of calcium ions is carried out by Ca2+-channels of plasma membrane and they are further transported by the xylem owing to auxins’ attractive ability. The level of intake and selectivity of calcium transport to ove-ground parts of the plant is controlled by a symplast. Ca2+enters to the cytoplasm of endoderm cells through calcium channels on the cortical side of Kaspary bands, and is redistributed inside the stele by the symplast, with the use of Ca2+-АТPases and Ca2+/Н+-antiports. Owing to regulated expression and activity of these calcium transporters, calclum can be selectively delivered to the xylem. Important role in supporting calcium homeostasis is given to the vacuole which is the largest depo of calcium. Regulated quantity of calcium movement through the tonoplast is provided by a number of potential-, ligand-gated active transporters and channels, like Ca2+-ATPase and Ca2+/H+ exchanger. They are actively involved in the inactivation of the calcium signal by pumping Ca2+ to the depo of cells. Calcium ATPases are high affinity pumps that efficiently transfer calcium ions against the concentration gradient in their presence in the solution in nanomolar concentrations. Calcium exchangers are low affinity, high capacity Ca2+ transporters that are effectively transporting calcium after raising its concentration in the cell cytosol through the use of protons gradients. Maintaining constant concentration and participation in the response to stimuli of different types also involves EPR, plastids, mitochondria, and cell wall. Calcium binding proteins contain several conserved sequences that provide sensitivity to changes in the concentration of Ca2+ and when you connect ion conformationally rearranged, thus passing the signal through the chain of intermediaries. The most important function of calcium is its participation in many cell signaling pathways. Channels, pumps, gene expression, synthesis of alkaloids, protective molecules, NO etc. respond to changes in [Ca2+]cyt, while transductors are represented by a number of proteins. The universality of calcium is evident in the study in connection with other signaling systems, such as NO, which is involved in the immune response and is able to control the feedback activity of protein activators channels, producing nitric oxide. Simulation of calcium responses can determine the impact of key level and their regulation, and also depends on the type of stimulus and the effector protein that specifically causes certain changes. Using spatiotemporal modeling, scientists showed that the key components for the formation of Ca2+ bursts are the internal and external surfaces of the nucleus membrane. The research was aimed at understanding of the mechanisms of influence of Ca2+-binding components on Ca2+ oscillations. The simulation suggests the existence of a calcium depot EPR with conjugated lumen of the nucleus which releases its contents to nucleoplasm. With these assumptions, the mathematical model was created and confirmed experimentally. It describes the oscillation of nuclear calcium in root hairs of Medicago truncatula at symbiotic relationship of plants and fungi (rhizobia). Calcium oscillations are present in symbiotic relationships of the cortical layer of plant root cells. Before penetration of bacteria into the cells, slow oscillations of Ca2+ are observed, but with their penetration into the cells the oscillation frequency increases. These processes take place by changing buffer characteristics of the cytoplasm caused by signals from microbes, such as Nod-factor available after penetration of bacteria through the cell wall. Thus, the basic known molecular mechanisms for regulation of calcium homeostasis in plant cells are reviewed. Data presented in the paper is important for understanding the role of calcium in the ions’ homeostasis and can be used for developing high-performance technologies of crops nutrition.

38-45

Authors: K. M. Bozhko

The article contains the results of determination of physical and micromorphological properties of soils under natural ravine vegetation in the southern part of Dnipropetrovsk region. The value of ravine forests for the steppe zone of Ukraine is analyzed, and the methods of investigation are shown. Forest typology characteristics of the vegetation stationary test areas, as well as macro- and micromorphological characteristic of the soil profile, structural condition of the soil, its aggregate composition, and water stability of aggregates, are determined. Soil-forming processes in ravine ecosystems of the southern variant in Dnipropetrovsk region are diagnosed. Micromorphological studies of soil in the intact state, as well as analysis of produced thin sections, revealed the high degree of aggregation of the upper (0–60 cm) soil horizons. Structure formation is of zoogenic origin. Large amount of soil aggregates of coprolite structure is clearly seen under the microscope. Well decomposed plant residues are visible in the aggregates. Soil over the entire area of the section is of dark brown, almost black color. This is due to the large amount (80%) of organic substances indicating the active processes of humification. Fine grained humus is represented by plenty of equally spaced bunches of humones. Humus is in mull form. Skeleton is composed of different sized minerals, with quartz and feldspars dominating in its structure. Plasma is of humus-clay type, uniform over the entire area of the section and anisotropic with point illumination. Visible pore surface area is significant (65%) in the upper layers of the soil profile. Pores feature round and oblong regular shape. Often (on 50% of the pore area) the outbreaks of small invertebrates are found. With the depth of the soil profile, visible pore area decreases, as well as the aggregation. While correlating with the micromorphological characteristics, water stability of the soil structural aggregates reaches very high (80%) indices in the upper horizons of the soil profile and gradually decreases with the soil profile depth. Active biogenic microstructure formation, defining significant aggregation and looseness of microstructure, was diagnosed.

53-59

Authors: O. I. Dotsenko

This paper deals with the peculiarities of functioning of murine erythron system under vibrational stress on the basis of experimental data about erythrocytes acid resistance. Experiments were made on the outbred male mice at about one age and weight that were maintained in vivarium conditions on usual diet. Animals were divided into 5 groups. Animals of 1–4 groups were exposed to daily thirty-minute vibration at frequencies of 8, 16, 24 and 32 Hz respectively, with amplitude of 0.8 ±0.12 mmduring 14 days. Animal exposure to vibration was provided by the electromechanical converter connected to the generator of low frequency signals. The fifth group of animals was not exposed to vibration and it was used as a control. Kinetic dependences of acid hemolysis of erythrocytes was registered daily, from the 1st to the 5th day, and further at the 7th, 9th and 14th days of experiment. Blood for analysis was taken from tail veins in 15–20 min after stopping of vibration. As the basic indicators characterizing resistance of erythrocytes to the hemolytic agent influence we used the hemolysis rate constant, i.e. the value inverse to cell half-life time. For analysis of acid erythrograms we also used such indicators as hemolysis duration, maximum erythrogram’s time and width of the interval of erythrocyte group dominating in the population. We processed the results of research statistically. The study showed that acid resistance of erythrocytes decreased during the first five days of vibration influence at frequencies of 8–16 Hz. Besides, erythrocytes were divided into fractions that indicated the erythrocytes aging and strengthening of the population heterogeneity. On the fifth day of 16 Hz influence the emission of reticulocytes was recorded. At 8 Hz influence these processes were registered on the 7th day of the experiment. During the subsequent days the hemolysis curves were slightly displaced in relation to the control. Increase in hemolysis time and forms of erythrograms suggested the existence of erythrocytes fraction with increased resistance to the haemolytic factor. High activity of stress-induced mechanisms led to the drop in the general erythrocytes content in blood, and to the decrease in the share of low-resistant “old” erythrocytes and general increase in erythrocytes stability to the acid hemolysis. At 24 Hz vibration influence we observed similar processes; however, during the second week of action the content of “old” erythrocytes in murine blood was much higher, compared with “young” cells. Strengthening of erythrocytes heterogeneity was observed with the shift on the erythrograms to the left, emergence of several maxima, and reduction of half-life time of the cells. However, the hemolysis termination time was not reduced. At 32 Hz vibration the erythropoesis was not observed within 14 days of the experiment. Stress-induced disorder of the hemopoesis and cellular composition of peripheral blood were revealed and expressed in erythropoesis suppression, devastation of the “old” erythrocytes’ reserve, and decrease in their acid resistance. The consequence of these processes can be hypoxia of cells and tissues, which is one of the mechanisms of organs stress injuries.

66-70

Authors: L. V. Gorobets, I. V. Matlaev

The work presents the results of the analysis of a species diversity of the Old East Slavic settlement “Igren 8”(Dnipropetrovsk, Ukraine). The settlement occupied the area of nearly 15 hawhich was relatively large for this region. In Medieval period around the mouths of tributaries to the delta of the Dnieperdense forests were located, although the region is located in the south forest-steppe zone and the steppe zone. The majority of hunted birds belong to the group Anatidae (at least 72% of the minimum possible number of individuals). Poultry played the minor role in the diet of the residents of the medieval settlement “Igren 8”. We have drawn the conclusion about birds from “Igren 8”inhabiting water with thickets of the hygrophyte vegetation on the periphery. Nowadays, there are many embryophytes such as Phragmites australis, Typha spp., Glyceria maxima, Acorus calamus and others in these places. Hygrophytes covering of reservoirs is typically less than 20%.

77-82

Authors: D. A. Bevzyuk, N. A. Levicheva

One of the most important problems of modern society is the growth of aggression which leads to crimes, sadism, violence and other antisocial actions. Therefore, the study of the mechanisms of development of aggressive behavior and negative aggressive reactions is extremely urgent. Thus, in order to correct the aggressive behavior it is extremely important to develop new methodological approaches. Previous studies have shown that the brain biopotentials provide functional transfer of information. With the help of magnetic or other information carrier, the information can be stored and transmitted remotely from the donor to the recipient and, in that way, can control the behavior of the animal body. Using of biological programs, expressed via the brain biopotentials at their minimum voltage (which is indicated by the amplitude of the frequency spectrum of electrical oscillations in the EEG), it can give therapeutic effect. The aim of the paper is studying of the neurobiological mechanisms of aggressive behavior and usage of bioinformatic programs expressed via the potentials of the brain. In the course of the experiments, we have shown the possibility to use the ventromedial hypothalamic stimulation as a realistic model of negative emotional state. In this model, behavioral indexes (reactions of avoidance, increased vocalizations, negative grooming) correlated with the indexes of electrical activity of brain structures of emotional limbic-neocortical system (numerous epileptiform paroxysms, sharp shocks and complexes with epi components of peak-theta and peak-delta type). The introduction of information expressed in biopotentials of the positive emotional ventrolateral hypothalamus of the brain of donor rat to recipient rats with a model negative emotional state leads to balancing of emotional homeostasis, resulting in disappearance of convulsive components and diffuse affective paroxysms in EEG, and also in manifestations of positive grooming and tranquility. This method of emotional homeostasis correction is suggested as a new method for correction of emotional disorders and is expected to be effective for the further study.

88-95

Authors: A. P. Pokhylenko

On condition of anthropogenic pressure soil biota is one of the first reacting on environment changes. As long as natural selection occurs by phenotypes, it is important that on the urban land the organisms’ adaptations to changes in natural factors can be revealed with phenetic methods. The paper analyzes the ecological modification of the diplopoda Rossiulus kessleri (Lohmander, 1927) in the Samarskyi Forest region environment (Novomoskovskyj forestry is the ravine ecosystem, and Kocherezhskyi forestry is short-term-flooded ecosystem) and State Reservation “Voloshanskaya Dacha” (“Zatishnoye”). Such investigation for this region is conducted for the first time. Space samples consisted of 30 individuals (males and females, proportionally) for each plot. Among others, 14 basic morphometric in-line parameters and its relation were chosen: length/width of the body, amount of segments, length of hindleg, length of telson, length/width of antenna, length/width of gnathochilarium, length/width of semiflosculous blades, length/width of promenthum, length of collum. Morphometric interconnections within the given populations were established with the help of the factor analysis. The most changeable morphometric characteristics between populations and sexes were revealed. For all the given populations sex dimorphism is pointed out for the size of gna-thochilarium and the length of collum. Basing on obtained results from specimen measuring from Novomoskovsky forestry district we pointed out that both the majority of the given in-line parameters and its relation had no sex dimorphism. It also shows the stability of the environment. It is estimated that females from Kocherezhskyi forestry population have longer antennae (males have 10,2% less) and body width (females are on 14,0% wider). Body width is stable characteristic for many Diplopoda species. With high signification level for both basic in-line characters (length and width), sex dimorphism is observed in the conditions of the State Reservation “Voloshanskaya Dacha” (“Zatishnoye” stow). ANOVA-test of the given data showed that two different groups existed. Specific characters for individuals with dispersal index 19,2% are extensive body parameters. Spatial population structure clearly distinguishes males from the general sample. Data obtained illustrates the anthropogenic pressure and can be used to monitor populations.