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Dynamics of fatty acid composition of total lipids was studied for freshwater salmon Salmo salar L. during its embryonic development from blastula (3 hours) up to hatching (108 days) as well as in unfertilized eggs. Stable amount of total and some saturated, monounsaturated and polyunsaturated fatty acids (PUFA) of total lipids was observed during embryonic development. Considerable changes in fatty acid composition were observed at the stage of prelarvae hatching, i.e., significant decrease of (n-6) PUFA (18:2(n-6) and 20:4(n-6)) and (n-3) PUFA and increase of total and some saturated and monounsaturated fatty acids was registered. Change in saturation ratio of membrane lipids justifies the presence of the biochemical mechanism forwarded on regulation of cell membrane enzymes in accordance with the changes of internal physiological processes taking place in the organism and fluctuations of external environmental conditions or the preparation period (as reproduction). Data on peculiarities of transformation and utilization of fatty acids during salmon embryonic development may be used for understanding of their functional role in the developing organism as well as for assessing the quality of the caviar.

The localization and morphological features of viscerosensory neurons of sacral spinal ganglia (SSG), innervating the colon, were investigated. In urethane anaesthetized cats, the solution of horseradish peroxidase was injected under the serosa of ascending and descending parts of the colon as well as of the rectum. After 48 hours animals were repeatedly anesthetized and transcardially perfused. Sections of SSG were stained according to Mezulam protocol (1978). All the regions of the colon studied were shown to receive afferent innervation from neurons of SSG SI, SII and SIII. Maximum number of the labeled cells was detected in SSG SII. The intensity of afferent innervation of the colon by the neurons of SSG was found to increase along its length in cranio-caudal direction.

Methods of thin-layer, gas-liquid, and liquid chromatography were applied to the study of the effect of various concentrations of aluminum and iron salts on the contents of phospholipids, cholesterol, and fatty acids in the aquatic invertebrate Hydropsyche contubernalis L. (Trichoptera). It was found that the effect of the metals under study on lipid contents in living organisms depended on the composition of the aqueous medium and concentrations of the metals. Aluminum and iron altered the value of the cholesterol-to-phospholipid molar ratio. In the absence of lethal effects, this was indicative of attempts to switch adaptational biochemical mechanisms to stabilize cellular structures.

We studied the preference behavior of slugs Deroceras reticulatum in experimental light, thermal, and salt gradients. The zone of each gradients preferred by the majority of individuals had the lowest contents of total lipids and total fatty acids in the tissues as compared to animals in any other zones. Hard gamma irradiation of slugs D. reticulatum proved to induce qualitative changes in salt preference, to decrease photoresponse in light gradients, and to increase lipid content in tissues.

Arachidonoyl dopamine and haloperidol, both separately and in different combinations, inhibit regeneration of the gastral and basal regions of hydra. In addition, both substances induce stable anomalies of morphogenesis in the form of outgrowths and additional tentacles in gastral regenerates. In the presence of both substances at different combinations, anomalies either do not appear altogether, or exist for a short time, thus suggesting the normalization of morphogenesis. Possible mechanisms underlying the effects of these substances are discussed.

The study was aimed at morphometric analysis of cluster organization of neurons, forming interzonal cortico-cortical connections within the visual cortex. The study employed the technique based on horseradish peroxidase retrograde transport and methods of mathematical analysis of spatial distribution of labeled cells. The quantitative characteristics of cell distribution were obtained including cluster volume and linear dimensions, distances between their centers of gravity, periodicity and distribution along cortical surface. Age-related peculiarities in the distribution of initial cells of cortical interzonal connections were found. It was demonstrated that adult cluster organization pattern was established by the end of the second postnatal month. Quantitative differences in the spatial distribution of neuronal groups in the visual cortical areas 17 and 18 were determined.

The influence of low pH (5.0 and 4.0) on lipid metabolism of caddisworms Hydropsyche contubernalis L. (Trichoptera) was studied in 48 h toxicity experiments. The results were correlated with lipid composition of caddisworms directly isolated from natural water. Phospholipids, cholesterol, mono-, di-, triacylglycerols, and fatty acids were detected by thin-layer and liquid chromatography. Minimal environmental changes were shown to initiate the biochemical adaptation mechanisms strengthening the cellular membranes through their condensation due to additional phospholipid and cholesterol synthesis. In the natural medium the adaptation processes are more active than in the artificial medium. More serious changes, such as pH decrease to 4.0, suppress the adaptation processes in the first medium and terminated them in the second one.

The effects of catecholamine synthesis inhibitors (alpha-methyltyrosine, 3-iodotyrosine, and alpha-methyl-DOPA) and dopamine receptor blockers (haloperidol and spiperone) on the regeneration of apical, gastral, and basal fragments of the hydra Hydra attenuata were studied. These experiments showed that alpha-methyltyrosine and 3-iodotyrosine significantly inhibited regeneration but did not produce morphological anomalies. Alpha-Methyl-DOPA produce less inhibition of regeneration, but induced ectopic tentacles and outgrowths in gastral regenerates. Haloperidol and spiperone had no significant effect on the rate of regeneration but induced significant numbers of morphogenetic anomalies in gastral regenerates. Apical and basal regenerates, which retained their natural organizers (the head and base respectively) never yielded morphogenetic anomalies in the presence of either dopamine receptor blockers or dopamine synthesis inhibitors. The possible role of neurotransmitters. particularly dopamine, in morphogenesis in hydras is discussed.

The development of cluster organization of neurons forming direct interzonal associative projections from striate cortex (area 17) to extrastriate area 21a in cat was studied by a technique of horseradish peroxidase retrograde transport. Reconstruction of cortical region containing retrogradely labeled neurons was performed using continuous serial sections of the brain. The analysis of spatial organization was done and quantitative characteristics of distribution pattern of initial corticocortical neurons in striate cortex in kittens were obtained. Interzonal connections were detected since 14th postnatal day. Neuronal cluster organization started forming after day 21 while its pattern became similar to that in the adult animal both qualitatively and quantitatively by the end of the 2nd postnatal month, that is somewhat later than it was previously thought. The data obtained also demonstrate the age-dependent decrease in the convergence of the striate cortex projections to area 21a associated with the reduction of the area, occupied by initial neurons.

Obvious inhibition of the hydra regeneration with no subsequent morphological abnormalities, was shown to occur when using alpha-methylthyrosine and 3 Jthyrosine. alpha-Methyldopa induced a slight inhibition but a considerable morphological change: ectopic tentacles, projections, bipolar forms in the gastric fragment. The apical and basal fragments did not suffer. The role of neurotransmitters in the hydra morphogenesis is discussed.

Spatial organisation and quantitative features of cortico-cortical neurons in area 17 that project to area 21a of cat visual cortex were investigated. We used the HRP technique and two-dimensional reconstruction from serial sections of brain. Pattern of distribution of labelled cells in some regions of areas 17 and 18, on the lateral and medial surface of the brain were analysed. The data about cluster organisation of cortico-cortical neurones, localisation, layer distribution and density of neurons were obtained.

We studied the effects of three inhibitors of catecholamine synthesis on the development of sea urchins Sphaerechinus granularis and Paracentrotus lividus. These drugs affected the early embryogenesis, which was expressed in inhibition of the cleavage divisions, appearance of abnormal embryos, and developmental arrest. The addition of arachidonic acid amide and dopamine to the incubation medium weakened the effects of the inhibitors. Spiperone induced developmental defects in preimplantation mouse embryos and sea urchin embryos. Arachidonic acid amide with dopamine exerted a protective effect against spiperone when introduced to sea urchin embryos at the blastula or late gastrula stages, rather than after fertilization. In murine embryos, this amide induced developmental defects and arrest itself and its effect was reversible. Possible mechanisms underlying the effects of these drugs are discussed.

We have demonstrated that viability of preimplantation mouse embryos F1 (C57B1/6 x CBA) after cryoconservation at the stage of four blastomeres improves after pretreatment with serotonin (5 HT, 5 microM) or total gangliosides of bovine brain gangliosides (TG, 3 microM) added to the cultivation medium. After thawing, 64% of embryos preincubated with total brain gangliosides and 49% of embryos preincubated with serotonin developed to the stage of blastocyst during the cultivation in vitro; in the control, no more than 25% of embryos reaches this stage, and all these embryos were abnormal. Possible mechanisms of protective action of these compounds is discussed. We conclude that mouse embryos subjected to freezing-thawing procedure can be used to examine the role of serotonin and gangliosides in the regulatory processes of mammalian preimplantation development.

The effects of the antitumor drug tiazofurin on development of sea urchins Sphaerechinus granularis, Paracentrotus lividus, Strongylocentrotus intermedius, and Arbacia lixula were studied. When 0.01-200 microM tiazofurin (TAF) was introduced in the incubation medium (artificial sea water) just after fertilization or at the midblastula stage, the development proceeded quite normally until the beginning of gastrulation. But later TAF blocked gastrulation and induced formation of mobile ball-shaped larvae with normal pigment cells but devoid of the nervous system, skeletal spicules and digestive tract. The threshold TAF concentrations varied from 0.05 microM (S. granularis) to 2-5 microM (all other species). When TAF was introduced during gastrulation and just after gastrulation, the larvae had defective nervous system and skeleton and suppressed expression of gangliosides. The nonhydrolyzable analog of GTP, GTP-gamma-S (5-20 microM), introduced in artificial sea water no later than at the midblastula stage prevented all above mentioned developmental defects.

The effects of acetylcholine antagonists on development of the two-cell mouse embryos was studied. Etpenal-3 and etpenal-14 were shown to delay cleavage, affect cytokinesis, induce fusion of the blastomeres and arrest development at the stage of two-eight blastomeres with respect to the concentration used. Atropine, an M-cholinolytic, affects the early embryogenesis at a higher concentration than the cholinolytics with mixed effect. Acetylcholine does not prevent cleavage and compactization of the embryos and exerts a protective effect against the cholinolytics with mixed effect at the early developmental stages. The effect of atropine is weaker. The data obtained suggest the presence of structures sensitive to cholinolytics in the early mouse embryos and a possible involvement of acetylcholine in the early development of mammals.

Radionuclide angiography was performed in rats with transplantable tumors (sarcoma 45 and Walker carcinosarcoma 256). Induced hyperglycemia was shown to result in blood flow inhibition in tumor and normal tissues of tumor-bearing rats. Some differences were revealed in a degree of reversibility of blood flow disorders in tissues of the above strains. The results obtained confirmed the advisability of radiation therapy at the height of a decrease in tumor blood flow.

The effect of serotonin and adrenaline antagonists was tested on the early embryos of mice of three lines. All the substances tested produced an arrest or inhibition of cleavage division and the appearance of anomalies. Serotonin introduced in the incubation medium was effective against some serotoninolytics. We were unable to test the protective effect of adrenaline, as in the concentrations used it has its own effect on the development. From the data obtained, a conclusion is made of the existence in early mouse embryos of the structures sensitive to serotonin and adrenaline antagonists. The assumptions is made from the previously obtained data on the presence of biogenic monoamines in early mouse embryos, of functional activity of prospective mediators of the nervous system at the earliest stages of embryonic development of mammals.

The effect of the physiologically active substances (histamine, serotonin) and their antagonists (bicarfene, cyproheptadine and preparation 407) on the growth of Chinese hamster fibroblasts in vitro has been studied. The cell survival evaluated from the number of colonies grown by the 7th day of cultivation served as criterion for the action of the substances under study. Determination of amines in fibroblast extracts was made by spectrofluorometry. It has been discovered that Chinese hamster fibroblasts are susceptible to a number of pharmacological preparations, antagonists of serotonin and histamine, and that histamine abolishes the inhibitory action of the respective antagonist on the colony growth. Biochemical analysis has shown that these fibroblasts contain tryptamine and serotonin and, tentatively, histamine. It is assumed that these endogenous physiologically active substances participate in the fibroblast growth control.

Using two fluorimetric techniques, identification and assay of indolylalkylamines have been made in sea urchin eggs and embryos. It was shown that serotonin-like substance of embryonic and adult specimens is not usually homogeneous and consists at least of two components, the main of them being presented by tryptamine or one of its derivatives with the replaced group at amino nitrogen. Serotonin is also present at all the developmental stages investigated although its concentrations are significantly lower. It is suggested that these substances are involved into regulatory processes during early embryogenesis.

During its fluvial life, the ovarian follicular epithelium of Lampetra fluviatilis undergoes polarity formation--in the animal hemisphere the follicular epithelium is flattened, in the vegetative--it undergoes a secretory specialization: as the secrete is accumulating, the follicular cells increase in volume and height, acquiring a cubical form. In connection with monotonous or differentiating morpho-physiological alterations of follicular epithelium within a single follicle during the period of rapid oocytic growth, it is suggested to widen the idea on kinds of its secondary transformation in the vertebrates. It is suggested to differ: 1) common secondary transformation, when secondary flattening (for example, in birds) or secondary specialization (for example, in fish demersal roe) embraces the whole epithelium of the follicle. In case of common secretory specialization, it can be a) isomorphous--at identical convertion of the epithelium in the whole follicle (for example, in sheatfish), b) dimorphous--when there is a certain difference in the character and degree of secretory specialization of the follicular epithelium in various follicular areas (for example in Myxine glutinosa); 2) unipolar secondary transformation when the follicular epithelium undergoes secondary flattening or secretory specialization only in the area adjacent to one of the oocyte poles (for example, in Lametra fluviatilis and Blennis follis). Follicular epithelium of the lamprey testis, unlike in other Anamnia, does not form spermatocysts; implantation of spermatids and spermia into cytoplasm of the follicular cells is not observed. Thus, histological structure of Cyclostomata testis is at a lower stage of development than in other Anamnia.

Antimycin A blocks cleavage divisions in concentrations 1-10-15-1-10-14 g/ml (experiments on Arbacia lixula) or 1-10-11-1-10-9 g/ml (experiments on sea urchins of the genus Strongylocentrotus). Subthreshold and threshold concentrations of this antibiotic do not affect the sensitivity of fertilized Strongylocentrotus intermedius to 1-benzyl-2, 5-dimethylserotonin, but increase their sensitivity to 5-butyltryptamine by a factor of 3-5. These data provide the basis for a discussion of the possible nature of the reception of serotonin and other low-molecular-weight regulators of early embryogenesis.