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21.
The activity of some enzymes involved in energy and carbohydrate metabolism was studied in Atlantic salmon embryos at the eyed egg stage and in salmon fingerlings (0+) from two trophic–ecological groups: the Varzuga River bed and two tributaries, the Pyatka and Sobachii rivers (Kola Peninsula). It has been demonstrated that heterogeneity of embryos was most evident in the case of cytochrome c oxidase (CO), malate dehydrogenase (MDH), glycerol-1-phosphate dehydrogenase (G1PDH), and glucose-6-phosphate dehydrogenase (G6PDH), while the lowest level of heterogeneity was observed for lactate dehydrogenase (LDH) and aldolase. A positive correlation was revealed between the activities of CO, LDH, MDH, and G1PDH. It was noted that G6PDH showed a negative correlation with almost all enzymes under study. It was found that salmon juveniles inhabiting the tributaries were characterized by high LDH, aldolase, and G1PDH activity and lower activity of G6PDH compared to the juveniles inhabiting the main river bed. Notably, the differences in the activity of the enzymes involved in aerobic metabolism between the two groups of fingerlings under analysis were observed only in the autumn.  相似文献   
22.
The estradiol content of muscles during metamorphosis in the daubed shanny (Leptoclinus maculatus) from different fjords of Spitsbergen Island, Svalbard, have been studied using mass spectrometry. The level of estradiol at the L4 larval stage of development is significantly lower than at the L2 stage. Values of this parameter in adults are significantly higher than in post-larvae (stage L5). Variations in the estradiol level during metamorphosis can be associated with the growth stimulation and regulation of the process.  相似文献   
23.
The activity of the key enzymes of the energy and carbohydrate metabolism (cytochrome c oxidase, lactate dehydrogenase, aldolase, and glucose-6-phosphate dehydrogenase) have been studied in the three-spined stickleback Gasterosteus aculeatus spawning in different biotopes of the White Sea (Sel’dyanaya Bay, Sukhaya Salma Strait, and Kolyushkovaya Lagoon). It was found that individuals of stickleback from different spawning grounds differed mainly in the level of anaerobic metabolism and in the degree of utilization of carbohydrates during glycolysis. The results testify to the existence of adaptive mechanisms for the restructuring of the metabolic pathways of the energy metabolism depending on habitat conditions in different biotopes during the spawning period.  相似文献   
24.
The content of total lipids, total phospholipids, and fatty acids of total lipids in muscles and liver of juvenile Lake Baikal sympatric coregonid fishes have been analyzed for the first time under a common garden experiment. Baikal omul, Coregonus migratorius Georgi, is an active migrant of the pelagic zones of the lake. Baikal (lacustrine) whitefish, C. baicalensis Dybowski, is a colonizer of the bottom habitats, which are relevant to the pelagic zones of the littoral and underwater slope. Structural lipids (phospholipids and cholesterol) dominated in total lipids of the tissues of all fish under study. Spare lipids significantly prevailed in omul muscles when compared to whitefish. The highest variability of fatty acid composition was reported in muscles of coregonid fishes. Statistically significant differences were revealed in the content of the ω3 polyunsaturated fatty acids in muscles of lacustrine whitefish and omul. Associations of lipid compositions revealed in tissues of the whitefishes under the study with their respective ecotypes have been discussed.  相似文献   
25.
Connections between the anterior thalamic and habenular nuclei were investigated in the lizard by administering horseradish peroxidase to these nuclei. They were shown to have overlapping locations of afferent sources, namely basotelencephalic structures, nuclei of anterior and hippocampal commissures, preoptic and lateral hypothalamic area, and superior raphe nucleus, as well as common projection zones, viz: the mamillary complex and the ventral tegmental area. Specific connections confined to individual nuclei were discovered, apart from those common to the nuclei: A reciprocal connection with the dorsolateral hypothalamic nucleus (for the anterior dorsolateral nucleus), a projection to the interpeduncular nucleus (for the habenular nucleus), and to the dorsal hypothalamic area (for the dorsomedial nucleus). No sources of afferent pathways to the anterior thalamic nuclei were found in the mamillary complex. All the thalamic nuclei studied, togetherwith their connections, are considered diencephalic relay links in pathways comparable with the dorsal (in the case of the habenular nuclei) and the ventral (with respect to the anterior thalamic nuclei) pathways of the mammalian limbic system.I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry, Academy of Sciences of the USSR, Leningrad. Translated from Neirofiziologiya, Vol. 19, No. 1, pp. 110–120, January–February, 1987.  相似文献   
26.
By Chromatographic separation of cytosol fraction of homogenates from gonads of females and males of green sea urchinStrongylocentrotus droebachiensis using an AcA-34 ultragel, protein fractions with mol. mass of 123 and 81 kDa are revealed, which have activity of calcium-activated proteinases. Dynamics of activity of the calcium-activated proteinases is studied during annual sexual cycles of the sea urchin. It is shown that the maximal activity of the studied enzyme in females and males of the sea urchin is present at the IV stage of gonad maturation, at the period of their trophic growth which is characterized by formation of stores of nutritient substances necessary for the subsequent development of embryos.  相似文献   
27.
The effect of two quinoline-N-oxide derivatives (2-(4′-nitrostyryl)-quinoline-l-oxide (2-NSQO) and 4-(4′-nitrostyryl)-quinoline-1-oxide (4-NSQO)) on modulation of microsomal NADPH oxidoreductase activity, nicotinamide coenzyme concentrations, and induction of apoptosis in K562 human erythroleukemia cells has been. 4-NSQO at the concentration of (10 μM) and 2-NSQO (10 μM) inhibited the activity of microsomal NADPH cytochrome c reductases in tumor cells by 15 and 50% respectively. Treatment of cells with these compounds for two days resulted in the activation of caspase-9 and caspase-3, the increase in ethidium bromide and 4′,6-diamidino-2-phenylindole (DAPI) fluorescence upon DNA binding, and induction of apoptosis. The latter was preceded by the decrease in intracellular nicotinamide coenzyme concentrations. The results obtained allow considering 4-NSQO (and its structural analogs) as perspective compounds for further experimental studies as antitumor agent with low toxic effect on tissues of an organism.  相似文献   
28.
29.
Water-soluble proteins from Aeromonas sobria, a causative agent of bacterial hemorrhagic septicemia of fishes, were separated into six fractions by gel chromatography on Sephadex G-100. Injections of fraction II (67 kDa) provided the highest protection of carps against the disease. Injections of proteins contained in fraction II caused stronger effects on certain biochemical parameters in the fish liver (fatty acids of phospholipids and cathepsin B and D activities) in comparison to infections of the live culture.  相似文献   
30.
Effects of patented mixtures of substances, used as drilling fluids in petroleum industry, on the activity of enzymes (cathepsin D, EC 3.4.23.5; catalase, EC 1.11.1.6; and DNase, EC 3.1.4.6) and the content of analytes (malondialdehyde, fatty acids, free and collagen-associated hydroxyproline, bile acids, and total protein) in liver, gills, muscles, gonads, and bile have been studied under aquarium conditions in mature river flounder and one-year-old salmon for the purpose of determining maximum permissible concentrations. Measuring 25-30 independent biochemical parameters per organ is sufficient for establishing a direct relationship between the concentration of an industrial toxicant and the integral biochemical index, a new characteristic defined as the ratio of the number of biochemical parameters significantly deviating from control values to the total number of the parameters measured.  相似文献   
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