[Postnatal changes of morphology of nerve and glial cells in neocortex of mice developing on the background of serotonin deficit].

It has been shown that deficit of serotonin during embryogenesis in rodents is accompanied by changes of morphological characteristics of neurons and glial cells at the period of postnatal development. A characteristic peculiarity of these changes is cell vacuolization that is of different expression in various cortical layers. In the experimental animals as compared with control ones, neurons of all neocortex layers have changed nuclei and a reduced volume of the cytoplasm. In neurons of upper layers, nuclei and cytoplasm contain occasional small vacuoles. In deep layers, vacuolization both of nuclei and of the cytoplasm is expressed to the much greater degree and vacuoles of large size are predominant. Results of immunocytochemical study have shown that in animals developing on the background of serotonin deficit there takes place a delay of the rates of formation and differentiation of astrocytic glia.

[Organization and cytochemical features of barrier structures in human placenta].

The aim of the present study was to investigate structural pattern of human placental barrier elements using light and electron microscopy and immunocytochemistry. Some important peculiarities of organization of the placental barrier were detected: difference in structure and amount of collagen IV in the basal lamina of endothelium and trophoblast, occurrence of smooth muscle actin in the capillary wall forming syncytiocapillary membranes. In the intercapillary stroma of terminal villi, both fibroblasts and macrophages but not myofibroblasts were found. Since smooth muscle cells and myofibroblasts are absent, pericytes are most likely cells to contain smooth muscle actin in the area of syncytiocapillary membranes.

[Structural organization of macrophages in forming human placenta].

Placental macrophages (Kashchenko-Hofbauer cells) belong to a special population of tissue macrophages of human fetal provisional organs. The aim of the present study was to investigate the structure of Kashchenko-Hofbauer cells at the stage of placenta formation using the methods of light and electron microscopy and immunocytochemistry. Cytological and cytochemical peculiarities of Kashchenko-Hofbauer cells revealed in this study, leave no doubt that they belong to the tissue macrophages group. Their cytoplasm is strongly reactive with antibodies against CD68 lysosomal antigen suggesting potentially high phagocytic activity of these cells. Weak nuclear labeling with proliferation marker PCNA was found in placental macrophages.

[Changes in the structure of the nucleus of neocortical neurons during deficiency of serotonin and catecholamines]. / Izmeneniia struktury iader neironov neokorteksa v usloviiakh defitsita serotonina i katekholaminov.

The study was taken on Wistar rats using selective neurotoxins 5,7-dihydroxytriptamine and 6-hydroxydopamine. The reaction of neocortical neurons to monoamine depletion was examined. Alterations in chromatin distribution and partial nucleolar segregation were detected in cell nuclei of some neurons. Peculiar intranuclear inclusions, persisting for a long period, are also found out. We propose that detected changes in the nuclear structure are due to intracellular adaptive reactions associated with alterations in nuclear-cytoplasmic transport and protein synthesis.

[Participation of intracerebral monoamines in intracellular processes in the neocortex neurons]. / Uchactie vnutrimozgovykh monoaminov v razvitii vnutrikletochnykh protsessov v neironakh neokorteksa.

Using complex of modern methods including histochemical and immunocystochemical ones, the reactions of monoaminergic pyramidal neurons to the injury of afferent inputs were for the first time established to be differently directed including dysadaptive reorganizations, death of part of the pyramidal neurons of layers II-III and adaptive reactions of cells of the same type of layers V-VI. Neuron death was different from apoptosis and from well known "dark" type of degeneration which suggests a special mechanism of monoamine induced death of neurons. Previously undescribed intranuclear inclusions in the form of vacuoles, vesicles, myelin-like and fibrillar bodies and filament bundles were detected in pyramidal neurons that react to the injury of monoaminergic systems. Nuclear, nucleolar and cytoplasmic reorganizations that are also present are indicative of the participation of monoamines in regulation of such intracellular processes as nucleolar activity, intensity of transcription and processing as well as of nucleo-cytoplasmic transport. These mechanisms mediate regulatory influences of monoaminergic systems on functional activity of main efferent neocortical neurons that participate in regulation of many CNS functions. The experimental phenomenon of selective sensitivity and death of the part of pyramidal neurons obtained for the first time is considered as a model for studying the pathogenesis of certain psychoneurological diseases, caused by monoamine deficiency.

[The participation of the serotoninergic system in regulating the activity of the central glutamatergic/aspartatergic and GABA-ergic synapses]. / Uchastie serotoninergicheskoi sistemy v reguliatsii aktivnosti tsentral'nykh glutamat/aspartatergicheskikh i GAMKergicheskikh sinapsov.

Selective lesion of the serotoninergic system diminished the synaptic uptake of 3H-L-glutamic acid and 3H-DL-aspartic acid, as well as the Na+(-dependent) binding of 3H-L-glutamic acid in the cortex and the brain stem. The data obtained suggest an ability of the serotoninergic system to modify presynaptic processes in amino-acidergic neurons of the CNS.

[Effect of ascorbic acid on the binding of 3H-GABA and 3H-glutamic acid to synaptosomes of the rat cerebral cortex]. / Deistvie askorbinovoi kisloty na prisoedinenie 3H-GAMK i 3H-glutaminovoi kisloty k sinaptosomam kory golovnogo mozga krys.

The effects of different concentrations of L-ascorbic acid (Asc) on Na+-dependent binding of 3H-GABA and 3H-DL-glutamic acid to rat brain cortical synaptosomes were studied. Asc, at a concentration nearly equal to brain extracellular one (3 X 10(-4) M), had no effect on specific and nonspecific 5H-GABA binding. At higher concentrations (10(-3) M) Asc strongly inhibited, and at lower concentrations (10(-6) M) considerably stimulated 3H-GABA binding. At a concentration of 10(-5)-10(-3) M Asc tended to decrease 3H-DL-glutamic acid binding.

[Intraventricular administration of 6-hydroxydopamine and ascorbic acid changes 3H-GABA absorption by synaptic endings of the cerebral cortex of the rat]. / Vnutrizheludochkovoe vvedenie 6-oksidofamina i askorbinovoi kisloty izmeniaet pogloshchenie 3H-GAMK sinapticheskimi okonchaniiami kory mozga krys.

Combined administration of 6-hydroxydopamine with ascorbic acid had no effect on 3H-GABA uptake in the rat cortical synaptosomes, whereas a significant increase of the latter was observed within 2 days after 6-hydroxydopamine alone. Ascorbic acid alone (20 micrograms in 20 microliter saline, bilaterally) significantly increased 3H-GABA uptake within 2 days and decreased it within 21 days. The data suggest that: catecholaminergic system may affect (directly or indirectly) cortical GABAergic neurons, and injection of ascorbic acid into lateral ventricles exerts an obvious effect on synaptosomal 3H-GABA uptake in the brain cortex.

[Content of N-acetylneuraminic acid in water-soluble and membrane fractions of various fractions from rat brain cortex]. / Soderzhanie N-atsetilneiraminovoi kisloty v vodorastvorimoi i mambrannoi fraktsiiakh tkani raznykh analizatorov kory golovnogo mozga.

The content of N-acetylneuraminic acid (ANA) was measured in the water-soluble and membrane fractions of the visual, locomotory, auditory and sensomotory divisions of rat brain cortex as well as in glycoproteins and glycolipids of the membrane fraction. The content of ANA in the water-soluble fraction of the visual, locomotory, auditory and sensomotory analyzers of brain cortex was 0.55, 0.56, 0.55 and 0.65 mkg/mg of dry weight, respectively. The ANA content in the membrane fraction was 9.2, 8.8, 8.2 and 8.4 mkg/mg of dry weight, respectively. The ANA content in the membrane fraction of glycoproteins was 2.8, 2.4, 2.2 and 2.8 mkg/mg of dry weight, respectively., that in the membrane fraction glycolipids--5.2, 7.2, 5.9 and 5.5 mkg/mg of dry weight, respectively. The ANA content in the membrane glycolipids of the locomotory division of rat brain cortex differed significantly from that of all the other divisions.